Tag Archives: wollastonite

The Wollastonite Group of Minerals

Published in the February 2017 WCGMC Newsletter

OK, I know, most of us have heard of the mineral wollastonite and many of us have collected it at the Valentine Mine in Harrisville, or at Rose Road in Pitcairn or Cascade Slide in the Adirondacks. You may even know that 100% of North America’s mined wollastonite comes from two quarries in New York, the aforementioned Valentine Mine and the Lewis Mine near Willsboro.  If you voted in the election of 2013, you may remember Proposition #5 in which the operators of the Lewis Mine sought to trade 1500 acres of their property for 200 acres in Adirondack Park immediately adjacent to the quarries west wall.

But did you know that wollastonite is just one triclinic silicate mineral within what is known as the Wollastonite Group?   These minerals are all single chain silicate minerals in which every third silicate tetrahedral is “twisted”.  Calcium cations connect parallel chains in wollastonite leading the chemical formula CaSiO3.  The lesser known members of this mineral group employ different elements as noted in the accompanying table.

Continue reading

Four days in St. Lawrence County

Prepared and published in the Wayne County Gem and Mineral Club News, October 2015.      WCGMC newsletter Oct 2015

Our 14th collecting trip of the year (but who is counting) was, surprisingly, the first official WCGMC venture to St. Lawrence
County in 2016.  But what we suffered in tardiness, we made up for in quantity.  The trip was four days long and included seven separate collecting sites (one, Rose Road, was visited by members on three separate occasions over the 4 days).  Several of us stayed in a rented home on Star Lake, owned by Anita Persson, wife of George Persson, who helped us with the Benson Mines visit during the trip.

The trip was not scheduled to start until Thursday morning September 17th, but Bill Chapman and I had arrived in Star Lake early evening on Wednesday and we decided to take Bill’s black light to Rose Road in Pitcairn for an early start.  As always the lower area, known to many as the purple diopside mound (or PDM), lit up bright yellow under long wave with the mineral scapolite and the albite at the “wollastonite skarn” (or green diopside mound) lit up red under short wave.

Continue reading

Valentine Deposit, Harrisville, NY

“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. Continue reading

Lewis Mine, Willsboro, NY

Article I published in March, 2014 WCGMC News

Mineral collectors appreciate the golden amber grossular garnet and green diopside offset by the brilliant white of the matrix wollastonite.  Students of SUNY-Plattsburg learn about contact metamorphism from Dr. Mary Roden-Tice during field trips to the locale.  Economic geologists appreciate the mine as one of only two active wollastonite producing mines in the United States, both of which are in New York State (the Valentine Mine near Harrisville is the second).  But to many New Yorkers, the Lewis Mine of Willsboro Township in Essex County, New York went about its annual production of about 60,000 tons of wollastonite (~10% of the world’s production) in quiet anonymity.

lewis mine 1

Continue reading