Collecting Copper in Michigan’s Copper Country

Field Trip: Copper Country Collecting in Michigan’s Keweenaw Peninsula

By Jeremy Zolan

Difficulty Level: Easy to Moderate

Supplies Needed:
Safety Goggles
Water
Sunscreen
Insect Repellant
Crack Hammer
Chisel
Shovel
Wrapping Paper for Specimens
Bucket
Sledgehammer (optional)
Prybar (optional)
Metal Detector (optional)

Description:

The Keweenaw Peninsula of Michigan has been nationally famous for over 100 years for its history of highly productive copper mining. The local basalt is criss-crossed with many thick veins of native copper that made up the main ore of many of the mines. Solid natural masses of copper weighing hundreds of pounds were found with relative frequency at the mines. Though these pieces certainly were the most valuable ore, the best specimens from the area are clusters of well formed copper crystals. Other metallic minerals can be found with the native copper such as silver, domeykite, mohawkite, and chalcocite. Many other interesting minerals like datolite, analcime, prehnite, agate, and thomsonite are also abundant in the Keweenaw Peninsula. While all the mines of the region are closed to copper production, many are maintained as museums and fee dig sites. There are also many abandoned mines in the area that can provide good digging in the dumps but be sure to acquire permission from landowners before visiting any location on private land.

Localities:

Central Mine:
US 41
Central, MI 49950

central_mine_Michigan
Photo by Dave Maietta

Map:

The large tailings piles of the Central Mine are visible from US 41 in Central, Michigan. Many collectors have had good luck recently working this location. Occasionally, contractors remove large quantities of tailings for construction purposes and this exposes fresh material. In addition to the standard copper specimens, copper included calcite and prehnite can be found here. Silver has also been found with copper here but it is rare. A metal detector is very helpful for sorting trough dump piles like those found at the Central Mine.

central_mine_calcite
Caption: Calcite with copper inclusions. Central Mine, Central, MI 4.9 cm x 4.6 cm x 4 cm Ex. Rukin Jelks Rob Lavinsky Photo

Caption: Unusually large copper crystal. Central Mine, Central, MI. George Vaux collection at Bryn Mawr College. Scale bar is 1” long with rule at 1cm. Rock Currier Photo.central_mine_copper

Caledonia Mine:
Website: http://www.caledoniamine.com/
906-370-1131
202 Ontonagon St,
Ontonagon
Michigan 49953

The Caledonia Mine is a fee dig site that requires an advance reservation. When digging at this site, collectors are given a large pile of stockpiled copper ore and tools to go through it. Weekly collecting events on Thursdays and Saturdays are also held from the first Thursday in June to the last Saturday in August on the ore pile. Advance reservations are needed for these too. The workings of the Caledonia Mine are impressively preserved and tours are offered too. The mine tours aren’t necessarily just geared for casual guests. Many kinds of tours are offered, some with a very in depth historical or scientific focus. It is best to check the museum calendar to see if any events are happening during the time of your visit.

caledona_copper
Caption: Representative specimen of native copper from the Caledonia Mine’s recent workings. 5.6cm wide. Rob Lavinsky Photo

A.E. Seaman Mineral Museum
Website: http://www.museum.mtu.edu/
Michigan Technological University
1404 E. Sharon Avenue
Houghton, Michigan 49931-1295
E-mail: tjb@mtu.edu
Telephone: (906) 487-2572

Michigan Tech’s A.E. Seaman Mineral museum is among the finest mineralogical museums in the world. Its laboratories are also critical in performing much of the cutting edge mineral research currently being performed. During the period of most intense copper mining in Michigan, many specimens of local minerals were donated to the museum. Their collection of Michigan minerals is the finest in the world and there is a strong local emphasis on their displays.

Check out our custom search and view all the minerals from Michigan for sale on eBay. Not only will you see lots of neat stuff for sale, you’ll also get an idea of what localities are producing in the region.

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Field Trip: Fluorite and Secondary Lead-Zinc Minerals from Marion, Kentucky

Field Trip: Fluorite and Secondary Lead-Zinc Minerals from Marion, Kentucky

Site Description:

The Illinois-Kentucky Fluorspar district is world famous for the enormous quantity of huge, gorgeously crystalline purple and yellow fluorite that originated from the now defunct mines near Cave-In-Rock Illinois. Just take a look at the amazing samples on eBay to get an idea of the current prices and selections. Many collectors do not know that despite the closure of the by far most significant fluorite localities in the region, there are still places in the area to find gorgeous fluorite. While many of these localities are abandoned mines that require deep underground exploration to retrieve specimens, the mines in Marion, Kentucky have specimen rich dumps that are easily worked by hand from the surface. While aesthetic material is plentiful, many of the workings are quite muddy and messy to dig in. It is important to keep in mind that while many gorgeous specimens can be had with minimal digging, specimens of similar quality to those seen in the nearby Ben E. Clement Museum, which features local minerals, are hard to find.

Perhaps the best central location to access all the mines in the region from is the Ben E. Clement mineral museum (http://www.clementmineralmuseum.org/). In the museum, they have many of the finest American fluorite specimens on display. Many are from the collection of the museum’s namesake- a giant in the local fluorite mining industry. It is amazing to see the near infinite color variation that fluorite possesses, especially the great diversity within the region. The museum has scheduled digs for fluorite and other kinds of minerals beginning late April through October. In addition to daytime digs, night digs for fluorescent specimens are held too. The museum can also arrange custom digs. Regardless, pre-registration is required.

Difficulty Level: Moderate

Supplies Needed:
Safety Goggles
Water
Sunscreen
Insect Repellant
Hand Lens
Crack Hammer
Chisel
Shovel
Wrapping Paper for Specimens
Bucket
Sledgehammer (optional)
UV Light (optional)

The Ben E. Clement Mineral Museum
205 N Walker St., Marion, KY 42064
(270)965-4263

Mineralogy:

The following is a list and brief description of common minerals found at the Marion area mines.

Calcite: A common gangue mineral. Rarely forms crystals good enough to keep. Often fluoresces red.

Cerussite: Very nice cerussite crystals come from the Marion mines and they are often overlooked. Forms colorless to smoky gray highly lustrous crystals associated with galena and hemimorphite. They either occur singly or are twinned and reach about 1cm in size. Crystals have diverse habits.

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Image: http://www.mindat.org/photo-207070.html Caption: Cerussite- Hickory Cane Mine, Marion, KY 17x13mm Steve Bonney Specimen and Photo

Fluorite: The most sought after mineral at the Marion mines. Found in sharp purple cubic crystals with a maximum diameter of about 3cm. Very easy to identify- the only purple colored mineral at any of the local mines. Found as micro to large cabinet sized specimens. The Marion area is world famous for fluorite.

0564800001161188076

Image: http://www.mindat.org/photo-76574.html Caption: Fluorite- Eureka Mine, Marion, KY Crystals to 7.5mm Peter Cristofono Specimen and Photo

Galena: Small cubes of galena to around 1.5cm can be found. Often they are weathered.

0563712001240270990

Image: http://www.mindat.org/photo-226066.html Caption: Columbia Mine, Marion KY 6x7cm Steve Bonney specimen and photo.

Greenockite: Rare naturally occurring cadmium sulfide that occurs as ochre colored powder with sulfide minerals, especially weathered sphalerite. Sometimes colors smithsonite yellow.

Hemimorphite: Hemimorphite forms druses of colorless to yellowish crystals in vugs and on weathering zinc minerals. Can cover areas to several cm with glittering crystals. Common, but often overlooked.

0323147001214866260

Image: http://www.mindat.org/photo-172178.html Caption: Hickory Cane Mine, Marion, KY 1.7cm FOV Steve Bonney specimen and photo.

Hydrozincite: Powdery white secondary zinc mineral. Fluoresces blue under SW UV light.

Quartz: Typically occurs as small drusy or isolated crystals to 4mm. Some are smoky.

Smithsonite: Ususally forms thick, liberal coatings of colorless to tannish botryoidal material. Some specimens are crystalline and some are yellow colored due to the presence of greenockite inclusions. Cabinet specimens are known.

0646119001274388453

Photo: http://www.mindat.org/photo-305765.html Caption: Marion, KY 7.5 x 6.5 x 5.8cm Rob Lavinsky photo

Sphalerite: Small aesthetic crystals of sphalerite to about 3mm are abundant. They are typically very lustrous and orange-brown in color.

By Jeremy Zolan

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Event Report- 2014 Castro Valley Club-Newark Pavillion Show, Newark, CA (Feb 21-23)

A Visit to the Castro Valley Mineral Club Show, 2014

By Jeremy Zolan – Earth Surgery

The Mineral and Gem Society of Castro Valley puts on an excellent small mineral show each year at the Newark Pavillion in Newark, CA. This small locally focused show great for all audiences and ages, and makes for a wonderful weekend outing especially with family and friends! This show attracts dealers who offer an extremely wide array of material ranging from gem and lapidary rough to rare minerals. There are also many displays and booths offering activities, information, and many other things in addition to those who strictly sell specimens. During my visit, everyone at this show was extremely kind and made me feel welcome to the California collecting scene which I am extremely new to. For new residents of California looking to make connections, this is a great springboard into the scene.

I have recently been staying in the the Barstow area of Southern California so getting to this show was quite a drive. It did allow me a first glimpse at the landscape of many interesting places I have never visited before and was very scenic. Here we have a picture of high desert scrub in Boron, CA with the titanic US Borax Mine lurking barely visibly in the distance. Many of the hills in the photo are partially made from giant tailings piles. This mine is not only famous for its incredible size and high production but for its mineralogy which is highly distinctive. In addition to producing many thousands of fine colemanite specimens, it also is well known for splendid examples of many rare borates such as inyoite, kurnakovite, probertite, and kernite.

Scrub Desert on the way to a gem show in california

Scrub Desert on the way to a gem show in california

The first thing I did when I arrived at the show was check out the display cases, which there were many of for a small local event. In my home New England region, events of similar size only rarely have as many displays so I was pretty surprised. The cases were filled by a local crowd including both collectors and museums but definitely far more of the former rather than the latter. Lapidary, mineralogy, paleontology, and anthropological themes were all present in the displays however there was a significant bias towards the lapidary side of things with comparatively very few mineral display cases. This was somewhat reflected in the abundance of lapidary dealers at the show though there were also many great mineral and fossil dealers as well.

Morgan Hill Poppy Jasper on Display

Benitoite and Neptunite Specimens on Display

Cabochons on Display by Mark Montgomery at the 2014 Castro Valley Show

Fremont California in the Pleistocene Era

Specimen of Columbian Mammoth from San Francisco

Next off, I decided to parouse the dealer booths and was pleased with the great variety in not only species and localities but prices I saw. There were many great specimens to be had for under fifty dollars including many lots of old material at multiple dealers that appeared to have not been repriced in decades. There was truly something for everyone at this event.

The first dealer I visited was The Uncarved Block which always has a good assortment of material though tends to mostly focus on classic, well known species that display best in the thumbnail to cabinet range. Many specimens stuck out to me but those pictured below were my favorite, most of which are things that rarely turn up on the West Coast.

First off we have two teal kyanite crystals in a biotite schist matrix from the Harts Range in the Northern Territory, Australia. The color indicates that the specimen may more precisely be from Huckitta Well or nearby. The crystals were aesthetically skewered through the matrix and had a very pleasing deep aqua blue color. The longest was exposed to about 6cm of its total length. The Harts Range is one of only a very small assortment of localities in Australia that produce gem pegmatite minerals such as beryl and garnets.

Kyanite Crystals in Biotite Matrix from Australia

Next, I spotted this specimen of beryl from Slocum’s Quarry in East Hampton, Connecticut. This very uncommon, very old, and now very closed locality is well known for its yellow beryl var. heliodor crystals which were opaque to extremely gemmy and sometimes formed in pockets. The pocket crystals were often etched in a manner similar to the Ukranian crystals from Volodarsk-Volinskiithough their color saturation ranges to an extremely deep and gorgeous pumpkin orange color. Slocum’s Quarry also exhibits an impressive suite of rare Be, Nb/Ta, and REE minerals. Ernie Schlicter collected the below piece which has bigger crystals than most by far even though they are of a very light color for Slocum’s.

Beryl in Quartz from Slocum Quarry, East Hampton, Connecticut

Romanian amethyst from Porkura, Huneodoara Co. is something I am always looking out for and in my opinion, are some of the world’s great amethysts with their extremely deep color saturation and unusual crystal shapes. They strongly resemble newer specimens from Guerrero, Mexico but being the snob that I am, I think the Romanian specimens always have better color. I really loved this piece which has the perfect balance of purple cityscape-like crystals and contrasting matrix. Truly a fine amethyst.

Purple Amethyst Crystals from Romania

Finally, I spotted this set of alphabet agate from Indonesia. The letters are formed by natural tubular inclusions of iron oxides and clays in the agate. These sets always amaze me. Imagine how many thousands of pieces must be sorted through to get a full alphabet! Truly a daunting task, it has been said to take years to find a full set by inspecting rough. Some letters such as R and Q with unusual shapes are apparently rarer than others.

Agate Alphabet Cab Set

It was then over to Earth’s Treasures, run by avid field collector Rick Kennedy. Rick has been working the California Blue Mine in San Bernardino County for aquamarine, topaz, quartzes, wodginite, and other associated species. This locality is outside of what is traditionally regarded as the Southern California Pegmatite district so I had to know more considering it could change our perception of pegmatite mineralogy in California. It appears that this pegmatite is of intermediate elemental distribution (LCT/YNF) though it is likely very lithium poor unlike some geochemically similar envirtonments though the micas would need to be analyzed to truly validate that statement. Greisenization took place in the top of the peg and created a lot of topaz and fluorite mineralization while deeper in were the nice gemmy aquas. Some of the crystals show interesting tapering that reminds me of specimens from Brazil and Argentina. Below is my favorite crystal from the locality he had for sale at his booth.

Aquamarine from the California Blue Mine

Rick had lots of other great material too; a lot of exotics especially. This limonite after magnetite pseudo is very peculiar especially. Considering Kansas is mostly sedimentary, one would not expect to see magnetite originating from there. Many of these magnetites were collected around 100 years ago.

Limonite after Magnetite Psuedomorph from Kansas

John Garsow had a lot of great material too with a focus on gem minerals, rough, and materials. John is also an avid field collector who has made some really nice finds in Southern California. He had this Chinese tourmaline that immediately caught my attention. If there is one group of minerals that China lacks it is pegmatite minerals. There are only two very poorly explored main areas for specimen producing gem lithium pegmatites in China; near Kashi, Xinjiang Uygur Province or the Gaoligongshan ranges in Yunnan Province. Both are located in notoriously remote and culturally distinct regions in western China. This piece, measuring in at around 8cm tall is from the latter which is known for mostly producing only tiny crystals to 2 or 3cm. Chinese specimens show frequent mislabeling so it is possible this is from another entirely different area since it does not resemble the majority of specimens I’ve seen from either Xinjiang or Yunnan Provinces. I thought it was a really fascinating piece for that reason.

Gem Green Tourmaline from China

Taking a break from strictly minerals, I decided to check out the Northern California Geological Society’s booth to ask some questions about local geology since I am by no means well versed in the geology of California which is extremely different from those good old passive margins on the East Coast that I’ve explored and collected in so much. Mostly, I was curious about the formation, petrology, and mineralogy of blueschists and eclogites; rare, extremely high grade metamorphic rocks I was rewarded with kindness and a very thorough explanation. NCGS offers many excellent field trip publications exploring many themes in the northern California area. They also have an excellent scholarship program for B.S through Ph.D.-level students in California and the adjacent states.

Origin of Ophiolite and Franciscan Complexes

Geologic Cross Section of Mt. Diablo

Glaucophane Schist from the Franciscan Formation in Marin County

Alfredo Petrov has long been one of my favorite mineral dealers for the scientific focus of his merchandise. In addition to specimens of many truly weird minerals, he often has specimens of odd reagents or elements. He had several vials and containers of selenium, calcium, lithium, and samarium. I encourage the sale of element samples at mineral shows. Element collecting was quite popular a few years back but seems to have tapered slightly at least in the US. As for minerals, hw of course had a lot of oddball specimens..in fact too much to mention. Some of my favorites were his tiny sapphires panned from Japanese alluvial gravels, analcime and natrolite with celadonite from East Greenland- far away from the famous mineral producing regions on the frigid island. I thought one of the nicer high end pieces he had was this English torbernite. It is priced very competitively considering the quality of the specimen, high pedigree A.E. Foote label, and overall rarity of the material.

Torbernite from Cornwall, England

I have been a customer of Mineralogical Research Corporation (Minresco) in the past so it was great visiting their booth and looking through some of their flats in person. They had lots of fine quality, well known material from worldwide locations displayed in the front of the booth and rarer specimens behind. As for the material out front, I thought their specimens of the new azurite find from Lavrion, Greece were some of the better I have seen. I did however spend most of my time looking at the rare material in the back flats which was perhaps the most varied material in the entire show. I will refrain from mentioning my favorites because there were just simply too many. I did think this vial of szabelyite from Bou Azzer Morocco was pretty cool considering it was probably collected and studied far before the mine produced the specimens it is currently famous for. It may likely be one of the earliest collected mineral specimens from Morocco in circulation. That may not be saying much though considering that the vast majority of Moroccan pieces are no more than 20 years old. I still thought it was very interesting to see.

Szaibelyite from Bou Azzer, Morocco

Uranium Minerals for sale at the Mineral Show

The 2014 Castro Valley Show was great fun and it was definitely geared to a wider audience than I feel most smaller local mineral shows tend to target. Not only was there great diversity of material available, but amazing deals to be had. Not only is this a great show for everyone interested in minerals as a hobby, but would be rewarding for dealers looking to obtain inexpensive, high quality material for their inventory. As far as improvements, my only big criticisms were that I wish the displays had better labeling and there was more emphasis on local field collecting in them. I cannot say the show had any other drawbacks for me considering its nature and size. I thought it was awesome!!! This is a great event that I hope continues to be held for many years in the future!

Below is a specimen purchased at the Show which is available from Earth Surgery – Contact at JZolanSci@gmail.com to inquire.

Uranopilite- Happy Jack Mine, Utah Ex. Dr. Eugene B. Gross PRICE: $

Uranopilite Glowing under UV Light

Uranopilite- $100
(UO2)6(SO4)O2(OH)6·14H2O
Happy Jack Mine, White Canyon Dist., San Juan Co., UT
Ex. Dr. Eugene B. Gross
6.7 x 2.4cm 21.81g

email JZolanSci@gmail.com to order

The rare uranium secondary uranopilite is rarely available in specimens as rich as this one where it is present as bright highlighter-yellow powdery masses in a dark sedimentary matrix. The uranopilite masses may be poorly defined crystals. Typical of most uranyl minerals, the specimen is vividly fluorescent in all UV wavelengths and slightly radioactive. The identity of this specimen is highly credible- this specimen resided in the personal collection of Dr. Eugene B. Gross; a geochemist who prospected the uranium deposits of Utah for the Atomic Energy Commission.

Uranopilite has a very odd structure in that it is a polymer composed of metal oxo-clusters linked by sulfate “couplings.” This phenomenon of uranyl-clustering is observed in a select few uranyl species and have some structural characteristics of formal polyoxometallates, which of only one occurs in nature. If you wish to inform yourself more on the cluster chemistry of they uranyl cation, especially in minerals, I recommend this paper: http://minmag.geoscienceworld.org/content/75/1/1/F3.expansion.html

To search for minerals for sale that were mined in California, check out this search for minerals of California on eBay

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UV Light usage in mineral collecting – A Review of a dual band light under $100!

I finally got tired of not having a UV light to use in the field. Years ago I had a nice unit with dual LW/SW and a 12v cigar lighter plug, which worked with lots of portable battery packs and in my car for those nighttime visits to classic UV locations. Sadly, this light was lost and replacing it would be a few hundred dollars.

But, you never know how much you miss something like a good UV light until it is gone. There are just so many things a UV light helps with when checking out minerals. From the visual identification to seeing if a purchased specimen is glued, a good UV light pays for itself, quickly.

I was excited to read about the improvements to UVTools.com handheld Lamp, an all in one unit with a long wave bulb and a strong short wave bulb powered by 6 watts, a decent output, for just under $100. The kit comes with the light, which requires 3D batteries, a sample of minerals to test the light with shortwave and longwave reactive specimens. Safety goggles and a cd rom with study guides and informative literature complete the package, all in all, it gives a great start to any beginner, while the advanced collector will appreciate the power this highly portable hand held unit produces. I found the LW light to be very bright and it made some of the fluorites in my collection to glow bright white/blue. The shortwave light gives a bright reaction, but typically from a distance of no more than 6 inches from the lamp. It will not light up a hillside, or even a whole flat of minerals, but it is perfect for “one on one” specimen viewing.

Below: Photos of the kit, the minerals that came with it and some UV reaction from those specimens.

UV Kit, includes the lamp, 10 mineral specimens, safety glasses and a cd full of information.

UV Kit, includes the lamp, 10 mineral specimens, safety glasses and a cd full of information. Available from http://UVTools.com

Shortwave Photo Sample two Calcite rhombs glowing bright red

Shortwave Light Sample (photo taken with Galaxy S2 Phone)

Longwave Light Sample (photo taken with Galaxy S2 Phone)

Longwave Light Sample (photo taken with Galaxy S2 Phone)

You can purchase this UV Lamp from the manufacture, directly at http://www.ultraviolet-tools.com for $99.99.

There were two interesting things I learned by using this UV light. This agate deposit near my house became that much more interesting when I found out that every single piece of agate glows bright green under shortwave light. That means there is a lot of uranium in the area, which is giving the agate that color. Then, a hill over from that agate deposit, at another agate deposit, the brown crust on some of the agates was determined to be an uncommon variety of feldspar, after it was found that these crystals, in micron size, were glowing bright pink, typical of the species. You might wonder, so what, crusts of brown on agate? Well, the sweet thing is that these agates would now glow three different colors, green, pink and orange, sometimes yellow, as well. Three color rocks are what it is all about, so being able to notice the brown crusty bits on some of the agates helps identify them for further UV evaluation! It should be no surprise, those glowing agates include the local petrified palm root and what I like to call “Manix Lakebed Agate” which is a slurry of reeds, roots, rods and roughage from the lake that got silicated into a variety of translucent gel agate in shades of clear to black with red inclusions to a thick jasper-like layered wad of organics in stripes of black, red, cream and white. All of these organic masses were ripe with uranium! Several uranium deposits dot the mountains to the south, UV light is a great indicator of “hot rocks”!

At WhereToFindRocks.com we give this product our recommendation for best starter kit for novices and backup/handheld for advanced collectors.
Just under $100.00 from a manufacturer who stands behind their product. http://UVTools.com

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Big Diamonds to be Found at the Crater of Diamonds State Park

3.85 Diamond Found at Crater of Diamond State Park
It has been a productive year at the Crater of Diamonds State Park. To date, October 26th, 2013, nearly 400 diamonds have been found over the span of the year, with some rather large ones, several over 2 carats. For instance, Oklahoma teen Tana Clymer found a beautifully formed 3.85-carat canary diamond on October 19th, very similar to the fine diamond that was found by the late Marvin Culver, also of Oklahoma, in 2006. That diamond, the 4.21 carat “Okie Dokie Diamond” has been featured in several books, magazines and has been on display to the public a few times. Another large diamond, a 5.16 carat diamond was found by 12-year-old Michael Dettlaff of North Carolina in August. A 2 carat brown stone was found in June and all of these stones have one thing in common…

Many of these large diamonds are often found on the surface of the digging area.

One of the things many people are shocked to see upon arriving at the park is the actual mine area. It looks like a freshly plowed dirt field, waiting to be seeded and farmed. This area is poked and prodded, pitted and flipped, in search of the small gems distributed in the dirt.
Digging for Diamonds at the Crater of Diamonds State Park Field

Finding the park is very easy, once you are in the general area of Murfreesboro, Arkansas you will see signs pointing to the famous state park. You pay a nominal fee per person and go out into the field to search. You can dig, collect dirt and screen it, looking through the mud for a glassy pebble.
Digging for Diamonds at the Crater of Diamonds State Park

Or, you can do what many of the people who find the large diamonds do, simply walk around the dirt field, looking for crystals that have risen to the surface.
Digging for Diamonds at the Crater of Diamonds State Park

Either way, the Crater of Diamonds State Park is a great place to visit and try your luck at finding a precious stone. The chance of finding one of these stones is stacked against you, but if you happen across one of those rare 2+ carat stones, the Associated Press would like to acquire your photo posing with the stone.

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