A Geoscience Digital Image Library

TitleGahnite and sphalerite from Franklin, New Jersey
DescriptionThis sample contains mostly dark brown gahnite, ZnAl2O4. If you look closely you can see a hint of gahnite's tendency to form octahedral (8 sided) crystals. The specimen also contains lots of brownish (harder to see, slightly lighter colored) sphalerite, (Zn,Fe)S, on top of the gahnite. Also seen in this photo is a small amount of the less common, reddish, variety of sphalerite that is sometimes called ruby blende. This sample, 11 cm across, comes from a well known mining district in New Jersey.
LocationUSA ▹ New Jersey. Near Franklin.
PhotographerNessa Eull. 2001-07-10.
CollectionUniversity of North Dakota Mineralogy Collection #178.
Key wordsruby blende, sphalerite, gahnite, New Jersey
Tech details774 KB. Hand specimen. Fujifilm FinePix S1Pro digital camera; 60mm AF Nikon micro lens.
GeoDIL number1087