Vote for your favorite mineral in #MinCup26! - Quartz vs. Asagiite It's a classic vs a newbie as the most common named mineral in the crust Quartz is up against an exceedingly-rare sea foam-green mineral discovered just a few years ago Asagiite.
xls rest either on feldspar or on smoky quartz. Helvite xls were found at Tongbei at the end of 2001 and the first xls collected had a dark surface coatings. Helvite xls discovered at later times lack the dark surface coatings but it is suspected that such pieces have been treated in Tongbei with HCl.
Wushan Spessartine Mine, Tongbei, Yunxiao Co., Zhangzhou, Fujian, China