Sandstone coaster sets of four, Arizona Sierra Pick your own...:L The dark iron bands are

The dark iron bands are harder than the surrounding sandstone and create ridges as the softer material is more quickly sandblasted away—just like the material would erode in nature

with a milky off-white color likely tinted olive-gray by hedenbergite

Ferruginous quartz is typically fairly opaque due to the density of iron oxide inclusions

tolerates variation

but it is lush with very clear large botryoidal hyalite

Sandstone coaster sets of four, Arizona Sierra Pick your own...:L The dark iron bands areLocale: Arizona Material: Arizona Sierra Sandstone Drink coasters, sets of four Approx size each coaster has a diameter of 3 2 3" and is 1 3" thick, backed with a 1. 5mm thick layer of cork padding. Approx weight each coaster weighs around 4. 75oz, for a set total weight around 18. 75 to 19. 5oz Sandstone is a porous rock that soaks up water, making it an ideal material for drink coasterscondensation easily absorbs into the rock without damaging it. I