Looming behind them, above the ruins of Rhyolite, were the purple Bullfrog Hills, scarred with the diggings of 10,000 men who made the town a roaring camp at the turn of the century.

“A large purple rhyolite flake, likely made of stone found in the Hingham area, is a great way to end a sunny day of archaeological survey at the First Church in Roxbury,” the post read.

Ioneer describes the Rhyolite Ridge project as the first new lithium mine in the United States in nearly 60 years. It will also be the first new U.S. boron mine in almost a century.