Chocolate dogtooth calcite, large Dragon's Blood Jasper which appears matte but glitters

which appears matte but glitters under direct light

Sandstone with distinct layering like this is often called ‘picture stone’ because the layers can resemble a southwestern landscape with open skies—option C is a good example

25 x 1 x 1"

and then through geological processes the aragonite was replaced with dolomite

Chocolate dogtooth calcite, large Dragon's Blood Jasper which appears matte but glittersLocale: Santa Eulalia, Chihuahua, Mexico Approx size: 4 x 3 x 2. 5" Approx weight: 652g (about 1 1 3 lb) Known by the trade name "chocolate dogtooth calcite," this type of calcite from the famed Santa Eulalia mining district grows in hedgehog clusters of sharp dogtooth (scalenohedral) crystals. The variety gets its distinctive opaque brown appearance from iron oxides; a layer of hematite included calcite is deposited on the surface during a later