Opal is a colorful mineral of hydrated form of Silica related to Quartz. It’s internal structure makes it diffract light, taking on many colors depending on the conditions when it was formed. Those colors can range from clear through white, red, orange, yellow, green, blue, purple, rose, pink, brown and black. Opal varies in optical density from opaque to semi-transparent. Opal is the national gemstone of Australia, a producer of over 93% of the world’s supply.
Dendrites are branched or tree like inclusions, usually manganese or iron oxides that are caused by irreversible aggregation of small particles forming large cluster. Dendritic crystal growth is common and resembles a snowflake formation or frost patterns on a window. Dendritic crystallization forms a natural fractal pattern. The term “dendrite” comes from the Greek word dendron, which means “tree”. It has only been in recent years that researchers have begun to understand how dendrites form and these ideas were developed by chemists and mathematicians working in disciplines called chaos and fractal geometry. Colloidal-sized particles move in random paths in a phenomenon called Brownian motion.