Willemite - image 1
Willemite - image 2
specimen video

Willemite

Unknown Owner
Willemite is a very rare zinc silicate species and yet of its few significant occurrences worldwide each has its own unique form, or appearance. At the world-famous Tsumeb mine in Namibia the classic Willemite is sea-green/blue in colour with a glossy wet-looking resinous lustre and typically forms botryoidal masses composed of many alligned tiny short prismatic crystals. This extremely rich example from Tsumeb presents a rather lovely curved thin layer of translucent Willemite crystals clearly representing a cast after some earlier mineral. Both the outer (convex) and inner (concave) surfaces are coated with fine glossy sea-green crystals and when held up to the light the superb translucency shows up really well. The inner surface is much brighter with small areas of blue-green Rosasite evident, whilst the outer edge is largely covered in a fine white dusting of Dolomite, with some tiny rhombic crystals visible. This is a very classy Tsumeb Willemite in superb condition and with an excellent sculptural form. Ex Weyand collection.

Product details

Species
Willemite, RosasiteAbout Willemite →
SizeSmall Cabinet
Dimensions6.5 x 8.9 x 2.8 cm
Added on09/20/2025
Locality
Namibia, Oshikoto Region, TsumebRegional guide →

Known provenance

DateCollectorAcquisition price
01/2026Unknown Owner$2,000.00
—Crystal ClassicsNot disclosed

Learn more

Willemite
Mineral guide
Learn about Willemite
fluorescent zinc silicate with UV glow; daylight colors range from colorless to pistachio, iconic from Franklin–Sterling Hill and Tsumeb.
Willemite
Regional guide
Willemite from Tsumeb, Namibia
Tsumeb willemite is the zinc silicate for collectors who usually think of willemite as a fluorescent-mineral classic from Franklin, New Jersey, and then discover that Tsumeb rewrote the aesthetic rules. Here, Zn2SiO4 appears not as massive ore but as glassy to sparkling crystal groups, botryoidal crusts, radiating sprays, delicate acicular “lawns,” and rare individual hexagonal prisms. The colors are equally un-Franklin-like: white, gray, yellow, green, blue-green, turquoise-blue, pale blue, reddish brown, and the much-loved champagne to honey tones. The best pieces have a crisp, jewel-like presence in daylight, often on white calcite or dolomite, with the color contrast that Tsumeb collectors prize.