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A Geoscience Digital Image Library

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TitleWillemite, quartz and franklinite from Franklin, New Jersey
DescriptionThe green mineral is willemite, Zn2SiO4. It is a rare mineral, but at Franklin, New Jersey, it is an important ore of zinc. Willemite is included in many mineral museum collection because it exhibits marked bright green fluorescence when seen under ultraviolet light. Specimens from Franklin may also contain calcite that fluoresces red, making them especially attractive. The black mineral is franklinite, (Zn,Fe,Mn)(Fe,Mn)2O4, a member of the spinel group. At Franklin it is mined for zinc and manganese. Whitish quartz is also present in this sample. The deposit at Franklin is unique and world famous. Many rare minerals are found there, some in large quantities. This sample is 5 cm across.
LocationUSA ▹ New Jersey ▹ Sussex. Near Franklin.
PhotographerDarla Sondrol. 2001-03-26.
CollectionUniversity of North Dakota Mineralogy Collection #1133.
Key wordswillemite, franklinite, New Jersey, Franklin
Tech details320 KB. Hand specimen. Fujifilm FinePix S1Pro digital camera; 60mm AF Nikon micro lens.
GeoDIL number257