Onyx is formed from dissolved carbonate minerals (usually calcite) when limestone or dolomite sediments come into contact with hot water.  Heat from recent volcanic activity causes this hydrothermal alteration and the dissolved minerals are then precipitated when these fluids reach the surface.  Precipitated carbonates from these hydrothermal solutions are called “flowstone” or travertine, as well as onyx.  Red, green and orange colors result from trace amounts of impurities.

This beautiful stone is from the Balochistan Province in Western Pakistan.  Skilled artisans in Karachi, Pakistan turn solid stone blocks on lathes to create beautiful bowls, vases and plates.

Onyx is soft with a hardness of 3.  So, can you use these items?  Vases are fine for flowers.  It is safe to drink wine out of our goblets, but you will see the inside of the goblet dull.  The beautiful polished  surface of bowls, plates and trays will stay shiny if used to serve dry items like crackers of popcorn.  Acid in food like salads, vegetables and soups will dull the surfaces they come in contact with.  Also, metal utensils will scratch the surface.  We recommend cleaning with a damp cloth. No microwave ovens or dishwashers, please.