17.29ct Opal Andamooka Matrix In 14K Yellow Gold Forged Wrap Total Weight. Matrix Opal is a permeable opal, which originates from Andamooka, South Australia. Matrix Opal is commonly color enhanced (carbon impregnated) by soaking it in sugar syrup and then heating it to carbonize the sugar.  This is referred to as 'sugar treated". This treatment darkens the opal and makes the color more prominent. This stone has been coated with a sealer.  Pictures are taken in different lights to show off the opal. Very nice gold and red fire, beautiful pendant. Total size of this pendant is 26 x 17 x 5 mm. Shipped Free with USPS First Class Package.