Artists Bisbee Velvet Beauty Azurite is a photograph by Bob and Nadine Johnston which was uploaded on September 12th, 2014.
Artists Bisbee Velvet Beauty Azurite
The name of this magnificent specimen, Velvet Beauty.... The Vender obtained this from a private collection and displayed it at the Quartzite Rock... more
Title
Artists Bisbee Velvet Beauty Azurite
Artist
Bob and Nadine Johnston
Medium
Photograph - Digital Painting - Save On 10 Or 25 Gift And Note Cards...
Description
The name of this magnificent specimen, Velvet Beauty.... The Vender obtained this from a private collection and displayed it at the Quartzite Rock and Gem Show probably the largest Rock and Gem show in the country.... Originally Found in a mine located in Bisbee, Arizona. Bisbee is a world renowned location for azurite, gold, silver, turquoise, copper, and may other minerals or gem stones.
Azurite was used as a blue pigment for centuries. Depending on the degree of fineness to which it was ground, and its basic content of copper carbonate, it gave a wide range of blues. It has been known as mountain blue. When mixed with oil it turns slightly green. When mixed with egg yolk it turns green-grey. It is also known by the names Blue Bice and Blue Verditer, though Verditer usually refers to a pigment made by chemical process. Older examples of azurite pigment may show a more greenish tint due to weathering into malachite. A chemical analysis of paintings from the Middle Ages shows azurite is being recognized as a major source of the blues used by medieval painters. True lapis lazuli was chiefly supplied from Afghanistan during the Middle Ages while azurite was a common mineral in Europe at the time. Sizable deposits were found near Lyons, France. It was mined since the 12th century in Saxony, in the silver mines located there.
Heating can be used to distinguish azurite from purified natural ultramarine blue, a similar but much more expensive pigment, described by Cennino D'Andrea Cennini. Ultramarine withstands heat, but azurite turns to black copper oxide. However, gentle heating of azurite produces a deep blue pigment used in Japanese painting techniques.
Azurite is used occasionally as beads and as jewelry, and also as an ornamental stone. However, its softness and tendency to lose its deep blue color as it weathers limit such uses. Heating destroys azurite easily, so all mounting of azurite specimens must be done at room temperature.
The color of azurite makes it a popular collector's stone. However, light, heat, and open air all tend to reduce the color over time. To help preserve the deep blue color of pristine azurite specimen, collectors use a cool, dark, sealed storage environment like that of its original natural setting.
Prospecting
While not a major ore of copper itself, the presence of azurite is a good surface indicator of the presence of weathered copper sulfide ores... It is found in with very similar malachite, producing a color combination of deep blue and bright green strongly indicative of the presence of copper ores.
The photo was taken through glass, and the vendor held up a flashlight for me to take this picture. Velvet Beauty can be yours for a mere $25,000. It is the finest specimen I have ever seen of one of my favorite minerals. I believe the chunk weighs about 3 pounds
Uploaded
September 12th, 2014
