3.4" Gemmy Grossular Garnets on Hedenbergite - Vesper Peak, Washington

Vesper Peak is located along the Sultan Basin in Snohomish County, Washington. It is known for producing exceptional grossular garnet specimens, as well as a wide variety of other minerals including quartz, prehnite, diopside, pyrite, calcite, clinozoisite, hedenbergite, and many more. The most commonly known mine is the 48-55 Mine, or the Garnet Mine, and the claim is owned by Mr. P. E. Crane of Snohomish, Washington. The hike to this location is considered quite difficult and is only accessible for about half of the year.

Hedenbergite is a calcium iron (magnesium) silicate that often bears a range of green to brown coloration. The crystals are typically opaque and occur in stubby or prismatic aggregates. Inner Mongolia, Russia, and Greece all produce quartz crystals colored green by fibrous hedenbergite inclusions. A variety of hedenbergite can be found in Sweden as well: green-black, blocky crystals come from the Nordmark Odal Field in Värmland County.

Hedenbergite was given its name in 1819 by Jöns Jakob Berzelius, a Swedish chemist. He named the mineral in honor of Anders Ludvig Hedenberg, a chemistry student and co-worker who originally discovered and described the mineral in Tunaberg, Sweden.

The general chemical formula of Hedenbergite is CaFe2+Si2O6 .