Australian solid black opal pendant set in 18k gold  and chain is gold plated. Incredible mixed of electric blue and green. The pendant measure 10 mm x 8 mm  ( opal size 5 mm in length ) Pendant top : Stamped 18k Chain : gold plated 40cm Opal is the national gemstone of Australia that produces over 90% of the world's supply.  Black opal is a natural solid stone with a black or dark grey body tone and black opals come from Lightning Ridge NSW Australia.