Home > California Borate Minerals – July 22 > MS0962 Ulexite "cottonball"

Ulexite "cottonball" - Sold


Ulexite is a complex sodium calcium borate mineral with triclinic symmetry. The name honors Georg Ludwig Ulex (1811-1883), a nineteenth century German chemist. Ulexite typically forms fine needles and fibrous masses, but most specimens do not survive much handling. This is a rare clump of needles, affectionately known as a "cottonball". While discussed in the classical literature, these form on the surface of salt flats, and provided easy picking for early miners. Few are preserved. This specimen carries a vintage "Greiger's Minerals" label dating to the 1946-1953 period. Fragile but still mailable.