Front:
NGTON
SEP
17
1992
20069
Minerafs USA
29
3.
Wulfenite
KOSL oW
Back:
WULFENITE
First Day of Issue: September 17, 1992
First Issue Location: Washington, D.C.
The importance of minerals extends well beyond their
usefulness as sources of metals. Minerals such as garnet
and corundum are used as abrasives in modern industries
throughout the world. Because of its high specific gravity
and its ability to make “heavy mud," barite is used
extensively by oil companies when drilling wells. Miner-
als have aesthetic value as well and are one of nature's
most exquisite art forms. Diamonds, rubies, emeralds and
sapphires are but a few examples of nature's elegant
minerals. Although not as well known, wulfenite is one of
the most beautiful minerals in the world. Named in honor
of Austrian mineralogist Franz Xaver von Wulfen, this
stunning mineral has a resinous luster and occurs in
various hues of yellow, orange, red and green. The red
crystals from the Red Cloud Mine in Yuma County,
Arizona are the most prized in the world. Wulfenite
occurs in oxidized zones of lead and molybdenum de-
posits. Very brittle and heavy, it has a hardness of about
3, and a specific gravity ranging from 6.7 to 7.0.
No. 92-116
First Day of Issue Postcard Collection™
©1992 Fleetwood® Cheyenne, WY 82008-0001
Original painting for the First Day of Issue Postcard by Howard Koslow
Heetwood
