6.5" Nipomo Sagenite Agate Slab - Freddie Quarry, California

This is a gorgeous, 6.5" wide, polished slab of Nipomo Sagenite Agate that was collected from Freddie Quarry in San Luis Obispo County, California. It is polished to a mirror-finish on one side and features beautiful fanning sagenite crystal formations that formed in association with marcasite. The marcasite can be noted by its metallic luster and is found along the edges of the rock at the edges of the slab. It has been thin sliced so that it can easily be backlit.

An acrylic display stand will accompany your purchase.

Sagenite agate is a formation of agate that contains acicular (needle-like) formations of fanning sagenite crystals that have been encapsulated in a mass of pseudomorphic agate. This occurs when agate fills a cavity within rock that had prior formations of minerals, in this case the golden sagenite crystal clusters. Specimens that come from Freddie Quarry in San Luis Obispo County, California can contain both formations of sagenite and metallic marcasite that formed in association, prior to being surrounded in agate.

Sagenite is a name that often refers to acicular rutile crystals, which in this case is accurate. The golden crystals within this specimen are technically rutile (TiO2) crystals.

Quartz var. Agate, Sagenite & Marcasite
Freddie Quarry, San Luis Obispo County, California
6.5 x 4.95", .18" thick