Show Report: 49th Annual Gilsum Rock Swap

by Jeremy Zolan – http://earthsurgery.tumblr.com

The Gilsum Rock Swap- http://www.gilsum.org/rockswap is one of the more popular New England mineral shows and is held in the rural town of Gilsum. New Hampshire. Gilsum is at the heart of an area very rich in pegmatites, many formerly mined for mica and beryl. New Hampshire has many great and diverse mineral localities. It is well known for its pegmatites which are both numerous and mineralized in rare species including several type localities most numerously found at the Palermo No. 1 Mine http://www.mindat.org/loc-3942.html. The miarolytic granites in the White Mountains region have produced many large, well crystallized pocket specimens of smoky quartz, amethyst, microcline, topaz, and rarer minerals such as arfvedsonite and danalite. Low temperature hydrothermal veins in the southwest corner of the state have produced fine fluorite crystals of a deep apple green color, notably from the William Wise mine- http://www.mindat.org/loc-4521.html.The Gilsum Rock Swap is an awesome way to celebrate the amazing mineralogy that New Hampshire has to offer.

In addition to being one of the few outdoor mineral shows in the region, a very large percentage of the material offered by vendors attending has been found locally. It’s also a great opportunity to catch up with field collectors and learn about recent finds and new localities. Swapping is encouraged at this show, so people often show up with their own personal finds to show off and trade. There were also two talks by Steve Garza on prospecting for mineral specimens and one by Bill Petronis on how to find Herkimer diamonds. I think it is great that the focus of the presentations is teaching practical skills in finding mineral specimens. The Gilsum Rock Swap is one of my favorite mineral shows and is still going strong after it’s 49th year.

This year’s Gilsum Swap was the first mineral show I attended as a dealer, however I did also take much time to look around and talk to local collectors. I am always amazed at the abundance of fine, local material available for unbeatable prices at this show; proof of that was the stock of Tom Minnich. Tom is an avid field collector and member of the Keene Mineral Club. He has collected many fine specimens throughouth New England, New York, and Nova Scotia.

A nice quartz cluster from Chesterfield Hill, Keene, Cheshire Co., New Hampshire. Specimens from here aren’t well known but quite nice. Some pretty big scepter quartzes have been collected from this near monomineralic vuggy low temperature hydrothermal quartz vein deposit in Clough quartzite. Tom is the guy to go to for these specimens.

Another nice quartz specimen from Diamond Ledge, Stafford, Connecticut. I really loved the aesthetics of this piece.

Tom also had this great large cabinet specimen from the now closed Green’s Farm Garnet Mine in Southbury/Roxbury Connecticut. Here’s a closeup view. This past year the property received a new land owner that does not approve of collecting in the mine. It’s a real loss for Connecticut’s mineral heritage- this used to be THE PLACE for taking people just getting into mineral collecting considering the abundance of well formed garnets at the locality.

There weren’t many new local finds from New Hampshire at the Gilsum Swap but Patrick Bigos from Midnight Minerals (http://midnightminerals.com/) had large, vibrant yellow fluorescing pieces of fluorescent manganapatite from the Ham and Weeks Quarry in Wakefield, NH. Yellow fluorescing manganapatite is found in many New England pegmatites but these specimens from Ham and Weeks are very large and brightly fluorescent.

A rare chance to get your own seventeen year cicada!

Here’s a specimen of beryl from an odd locality- Cucumber, Maine!! Robert Batic had bits and pieces from several old local collections at the show featuring many interesting locality pieces and some old classics too.

Mr. Batic also had this huge actinolite specimen from the Carlton Talc Mine in Chester, VT. Some big crystals on this one!

Friends from Mindat Linda and Don Kauffman of Lindon Mineralogy had a lot of esoteric New England material. Of particular note was this small well-formed triphylite crystal from the G.E. Smith Quarry in Newport, NH.

Rocko Minerals had quite a few awesome Herkimer diamonds with calcite, dolomite, and pyrite from the Benchmark Quarry. These came from an old and very fine collection of Herkimer material. This locality formerly produced amazing Herk combination specimens but is now totally off limits to collecting. It’s tragic that amazing pieces like this are now just tossed into the rock crusher!

Rocko also had this huge baryte crystal with pyrite from the Niobec Mine in Quebec- this carbonatite hosted niobium mine is famous for giant crystals of baryte. This is a pretty good one.

My former mineralogy and petrology professor Dr. Peter Nielsen of Keene State College showed me this wonderful scepter topaz from the Kandahar Mine in Braldu, Pakistan

Dr. Nielsen knows that I enjoy unusual specimens more than anything else, so he showed me these two great specimens of Heulandite-Ca from the type locality of Torch Hills, Scotland. I’ve never seen specimens from this locality in person! Apparently they were collected within a day’s time from the base of a dam when the water levels were unusually low.

D. Robinson Minerals usually has amazing things from unusual localities. My favorite that he had were his Korean specimens. Here’s a schorl that was collected right outside of Pyongyang before the Korean War.

The Pamir Mountains in Tajikistan have some rich pegmatites that unfortunately don’t produce many specimens. This tiny rubellite with a foitite (not proven but likely) cap show the kind of potential the region has.

Doug also showed me this Yaogangxian piece that featured both twinned bournonite and twinned fluorite crystals!

Wayne Corwin of Toveco is an avid Mindat member and always a familiar attendee of the Gilsum Swap. Wayne mines the Tripp Mine in Alstead, New Hampshire for aquamarine specimens and gem rough. He also encounters specimens of other material such as almandine garnets and schorl at this mine. He showed me some especially large trapezohedral almandines in matrix.

Jim Tovey of Toveco had several specimens of amethyst from Hopkinton, Rhode Island at his booth. This large cabinet specimen was probably the best of them

The 49th Annual Gilsum Rock Swap was yet again a great event! Although it was not as busy as it has been in previous years, it was still a lot of fun. Some pros: strong emphasis on locally sourced material and a great place to talk to other collectors to learn about New England mineralogy and mineral collecting. Quaint, peaceful setting in a small New England town. Cons: There were no booths primarily focused on swapping despite the name. In previous years, the show sponsored collecting trips to local pegmatite mines. Now unfortunately, most if not all the pegmatite mines in the vicinity of Gilsum are technically off limits to mineral collecting. You can buy maps to many of these localities at the show but you can’t actually visit most of them. I’d like to see accessibility to these localities change in the future. Celebrating the local pegmatite mines is the reason why there is a mineral show in Gilsum, after all.

On my way home to Connecticut, my collecting partner Mike, and I found a new locality for titanite crystals at a large construction site near Waterbury, CT. Above you can see many orange brown titanites to 4cm in a coarse grained amphibolite matrix. They were also granules of purple fluorescent scapolite associated with the titanite. I just thought I’d throw this picture into the report because it was such an interesting find!

Here at Wheretofindrocks.com, we encourage all of our visitors to visit a local rock show! You can be sure, there is one around your area at some point in the year! Check out the BEST Rock and Gem Calendar online on The-Vug.com