Agate and Amethyst Slice on Stand Magnets and lapis lazuli were just

and lapis lazuli were just some of the precious materials used in many of the pieces

Although a prismatic habit is typical of quartz

the artist

we see opal growing in chalcedony

Agate and Amethyst Slice on Stand Magnets and lapis lazuli were justAgate is a form of quartz known for its circular banding. It forms in layers over millions of years as groundwater with mineral impurities drip into empty spaces in volcanic and metamorphic rock. The different colors in the layers are due to different concentrations of minerals that form that layer. If you look at geodes, youll notice that the base or outside of the geode is composed of agate.