Sunday, January 4, 2009

Happy New Year To All Del-Air Members and All Interested Guests! Please scroll below to see a calendar of events for this years happenings in Quartzite, AZ. I do not know who posted this but I send out a hearty Thank You as this is useful information for rockhounds to have.

And now.........January 2009's Mineral of the Month.........'WULFENITE'

Discovered in 1845, the mineral Wulfenite, is named after Austrian Jesuit mineralogist Franz Xavier von Wulfen, who authored a monograph on the lead ores of Bleiberg, Austria. Wulfenite forms square shaped, tabular crystals and also prismatic crystals. Other habits are massive and granular. Wulfenite is typically colored orange or yellow but may be brown, gray, or greenish brown. The colors often appear brilliant. Wulfenite forms in the parts of the ore veins that have been altered by circulating fluids, mainly water. Wulfenite can occur with a great variety of other minerals, including cerrusite, limonite, vanadinite, galena, pyromorphite, malachite, and mimetite. Wulfenite fuses easily. It is soluble in heated hydrochloric acid but will dissolve much more slowly in cold acid.

It's chemical properties are as follows:

Group: Molybdates
Crystal Structure: Tetragonal

Chemical Composition: PbMoO4
Hardness: 2-1/2 to 3 Mohs Scale
Specific Gravity: 6.5 to 7
Cleavage: Distinct Pyramidal
Fracture: Subconchoidal
Luster: Vitreous
Transparency: Translucent, Opaque
Streak: White
Tenacity: Brittle

Melting Point: 1065 o Celcius