Sphalerite is the major ore of zinc and often found with the mineral Galena. When it is in pure form, with little or no iron, it produces clear to translucent crystals. The colors found in this mineral will vary, the pale yellow color is known as Cleiophane. The orange and red shades are known as Ruby Blende or Ruby Jack. Specimens with high iron content form dark, opaque metallic crystals which are dark grey to black and are known as Marmatite or Black Jack. Some specimens have a red iridescence within the gray-black crystals, these are called "ruby Sphalerite." Sphalerite is also known as Blende or Zinc Blende. It makes an interesting and attractive cabinet display specimen. It can have excellent luster and enhances many other beautiful minerals.
Other Zinc Ores include Hemimorphite, Smithsonite, Willemite, Franklinite and Zincite. Although Sphalerite’s importance as a Zinc Ore is well known, it is a very attractive and definitely interesting mineral for collectors as well. Gemmy, pale specimens from Franklin, New Jersey are highly fluorescent peach-orange and/or blue under long wave ultraviolet light (LWUV) and are known as Cleiophane, an almost pure variety.
Another interesting variety of Sphalerite found in Europe (Poland or Germany) is known as Schalenblende. This is a banded variety associated with Wurtzite and often also Pyrite and Galena that forms patterned concentric shapes. It is usually cut into slabs and polished, which are very popular with collectors. Schalenblende is also fluorescent displaying a peach-orange color under long wave ultraviolet light.
XXL specimen of Marmatite variety of Sphalerite with Dolomite
Excellent specimen of Marmatite (which is an Iron rich variety of Sphalerite) with Dolomite from the famous Brownley Hill lead and zinc mine in Nenthead, Cumbria, England. The mine operated from circa 1735 to 1966 under several different mining companies.
This specimen was previously owned by Teresa Rocks and Dan Weinrich-Fine Minerals (label included). Large specimens of Marmatite are rare and difficult to find.
weight: 5.07 lbs (2301g) measures 7.2 x 6.6 x 4.4 inches (18.4 x 16.9 x 11.2cm)
XL Sphalerite on drusy Quartz from Shuikoushan Mine, China
Majestic Wine Red Sphalerite crystals adorn this specimen which has randomly stacked natural host rock plates with a coating of drusy quartz that has burgundy colored undertones accenting excellent clear to white quartz crystals. There are also a couple of galena crystals on this piece that is from the Shuikoushan Mine in the Hengyang Prefecture, Hunan Province, China. This specimen is from our personal collection
This piece weighs 19.9oz or 1.24lb (565g) and measures 4.8 x 3.4 x 3.1 inches (12.3 x 8.6 x 7.9cm)
Photos taken with Nikon Coolpix L1 outdoors in natural sunlight & shade to show best color and details.
Rare Old Stock A+ Ruby Jack Sphalerite on Matrix from Missouri
Rare Old Stock A+ Ruby-Jack Sphalerite on Matrix from Missouri
Exceptional Large Ruby Jack Sphalerite crystals in a field of Majestic Wine Red Sphalerite crystals are the attractions of this Old Stock specimen from Missouri. Specimens showing large black-red crystals with definable triangular faces and twins have not been found in the Missouri area for over 50 years. This specimen is from our personal collection. (Last photo shows old spots with glue and styrofoam on specimen bottom from 1950's era mounting)
This piece weighs 11.7oz or 0.73 lb (332g) and measures 3.5 x 3.2 x 2.6 inches (9 x 8.3 x 6.8cm)