The Madawaska Uranium Mine in Bancroft, Ontario, has produced many fine minerals specimens over the years. Minerals, such as calcite, gypsum, fluorite, datolite, beta-uranophane and olioclase, have be found as fine crystals, some of which can be faceted into gems. The oligoclase gems offered for sale here were collected many years ago. In 1981, I had the opportunity to visit this mine while it was still in production. The Madawaska Mine closed shortly afterwards and remains closed. Read more.

Oligoclase is a feldspar and as such has a hardness of 6 along with 2 direction of cleavage. These properties mean that oligoclase is best suited for earrings and pendants.