Black Mica Muscovite 12mm Round - 15-16 Inch Size_3-9mm Agate is one of many

Agate is one of many varieties of banded Chalcedony

red and brown

and because its hardness has made the stone perfect for beads and cabochons

It also brings good fortune and attracts healing spirits

a cryptocrystalline Quartz

Black Mica Muscovite 12mm Round - 15-16 Inch Size_3-9mm Agate is one of manyMica is a mineral name given to a group of minerals that are physically and chemically similar. They are all silicate minerals, known as sheet silicates because they form in distinct layers. Micas are fairly light and relatively soft, and the sheets and flakes of mica are flexible. Mica is heat resistant and does not conduct electricity. There are 37 different mica minerals. The most common include: purple lepidolite, black biotite, brown phlogopite