Inorganics

Id	Identification Type	Name	Description	Distinguishing Features	Tags
59	Mineral	Vivianite	Blue in both plane and cross-polarized light. May occur in diagenetic sprays, euhedra, nodules, and coatings. Low birefringence. In core face, chalky white when reduced; bright blue when oxidized. Associated with organic matter, bones, teeth, seeds, and other environments with available phosphate and reduced iron. Commonly found in lacustrine and estuarine sediments. Not common in marine sediments.	Blue Pleochroic	phosphate transparent diagenetic ferrous
27	Mineral	Volcanic Glass	Transparent colorless to pale gray, green, or brown. Nonpleochroic. Isotropy is diagnostic feature, although devitrification may cause low-order birefringence at edges of grains. Moderate relief. May have bubble or pipe vesicles, stretching textures, cuspate to lunate bubble wall shards with sharp edges. May be disseminated throughout other sediment or occur in pure layers. Tephra may also contain crystalline grains from the same eruption or reworked material.	Isotropic Vesicular	bubbles shards sharp ash

Contact Information