This is Tremolite var. Hexagonite, and according to one ...
Description: This is Tremolite var. Hexagonite, and according to one reference it comes from the Type Locality (For Hexagonite) in Edwards, Balmat-Edwards Zinc District, Saint Lawrence County, New York. It is 3 1/2" x 2 /1/2" (8.89 cm x 6.35 cm)