“Site of the Month” article for Dec. 2014 WCGMC News
You can call it the Gouverneur Talc Company No. 4 Quarry, you can call it the Valentine Mine, or you can just call it that quarry off route 3 south of Harrisville, NY. Regardless of the name, in the business of wollastonite, the small quarry/mine in extreme northern Lewis County is pretty important. Together with the Lewis Mine of Essex County (see Feb 2014 entry on this website), the two quarries provide all of the US production (and 10% of the world’s supply) of the industrial mineral wollastonite.
As an operating quarry, the site is not generally conducive for collecting, however one of the field trips associated with the New York State Geologic Symposium this past October included a two hour stop and a visit to the quarry floor (Robinson and Chamberlain, 2014). Steve Chamberlain and George Robinson led the trip and given their past work on the mineralogy of the locale (Chamberlain et. al., 1999), those of us who participated learned a lot in the brief time we were there.The primary minerals at the location are not rare, nor do they occur in particularly well formed and/or terminated crystals. However, they can be both colorful and appealing and, therefore, collectible. Given its purity the mineral of economic importance, wollastonite, is brilliantly white. In its skarn setting the crystals can be large, and occasionally terminated, but in their fibrous and intergrown state, they do not stand out in the mineral case. Much of the recrystalline calcite flanking the wollastonite “ore” is a very deep blue color, but surfaces are all cleavage faces and not crystals. They are pretty in the garden and great examples of calcite’s rhombohedral cleavage, but not highly desirable for a collector of calcite crystals. In places the calcite contains small to moderate sized flakes of steely grey graphite and if the rocks break just right and you collect with care, these flakes show as intricate rosettes that do make the list as keepers.
The location is also well known for its interesting and, in some cases, rare mineral assemblage, much of which is found as micromount material within massive yellowish green prehnite that runs through both the calcite and the wollastonite.
In addition to acicular prehnite crystals, these vugs can hold small prismatic hedenbergite crystals, brewsterite-Ba (a rare zeolite), babingtonite and apophyllite. When I peer into some vugs in my specimens, I am sure I have some of these species, but I will need some help to identify them for certain. There was very fine drusy quartz along some fractures, but I did not see any of the nice hematite stained large quartz crystals for which the location is known (Robinson and Chamberlain, 2014).
The Saturday NYSGA trip also visited the Farr property in Natural Bridge and the Rose Road skarn in Pitcairn, a whirlwind visit to “three and a half skarns” in one busy day.
Although the quarry itself is not open to collecting, the operators do restock a pile of mixed material from the quarry just outside the main gate on Hermitage Road. It is worth a quick stop if you are passing through Harrisville on Route 3. In addition to the skarn mineral suite at the location, there is usually some unakite available.
References:
Chamberlain, S.C., King, V.T., Cooke, D., Robinson, G.W., and Holt, W., 1999, Minerals of the Gouverneur Talc Company #4 Quarry (Valentine Deposit), Diana Township, Lewis Co., NY, Rocks and Minerals, c. 74, p. 237-249.
Robinson, G.W., and Chamberlain, S. C., 2014, Three and a Half Skarns, in NYSGA 86th Annual Mtg. Guidebook, p. 98-112.