Hemimorphite

Description

Hemimorphite has a hardness of 4½ – 5 and a specific gravity of 3.475. It was “named in 1853 by Adolph Kenngott in allusion to the hemimorphic morphology of the crystals. Many names were previously assigned to this species, including calamine. Hemimorphite was chosen by the International Mineralogical Association, over calamine, in 1962” according to Mindat.

There’s a ton of Hemimorphite found around the world. In fact, can’t even tell you how many localities have been reported to Mindat, as the map keeps timing out, but there’s definitely a lot! However, not all Hemimorphite looks like this. It’s mostly and usually much more blue, at least, judging from the 3,500+ photos on Mindat.

According to Wikipedia, it’s been mined as a Zinc ore, “Hemimorphite most frequently occurs as the product of the oxidation of the upper parts of sphalerite bearing ore bodies, accompanied by other secondary minerals which form the so-called iron cap or gossan. Hemimorphite is an important ore of zinc and contains up to 54.2% of the metal, together with silicon, oxygen and hydrogen. The crystals are blunt at one end and sharp at the other.”

This was also once in the Dan Benke Collection, and for a little about him, the following two paragraphs were taken from the Earth Science Club of Northern Illinois:

Dan was an Associate Photographer of both the Mineralogical Record and Rock and Minerals magazines. He was a member of the Board of Directors of the Friends of Mineralogy from 1990 to 1993. He served as the Micromount chairman of the Midwest Federation of Mineralogical Societies from 1981 to 1988. At one time, he was an active ESCONI member with a deep interest in photographing microminerals. He served several terms as chairman of the micromount study group of ESCONI. He collected and photographed microminerals for over 30 years. His collection numbers over 14,000 specimens representing in excess of 750 species from localities throughout the world. The picture above is from his presentation at the Copper Country Mineral Retreat in 2009.

His biggest loves were photography, microminerals and book collecting. Dan began collecting & photographing microminerals, developing that technique to a high art. His photographs have illustrated many articles, and Rocks and Minerals journal covers, as well as in The Mineralogical Record and in the Los Angeles County Museum’s Photo Atlas of Minerals. He was an author and lecturer and was inducted into the Micromounters Hall of Fame.

It’s a smaller specimen, but it’s stunning! It’ll look great in your collection of other Colorado rocks, or as a prime example of Zinc as it’s naturally found!

Regardless of its purpose, this rock can’t wait to come home with you!