57769560_s_Facet_Rough___PrettyRock_com__Fact
[#] 8 [Myth] Only untreated, natural gemstones are valuable. [Fact] 
Many treated natural gems are very valuable, and some synthetics are not cheap. Take Paraiba tourmaline for example, which can be heat treated and still worth $1000's per carat.
Gemology, Gem Rough,Gemology,Gem Identification Tools,Facet Rough - PrettyRock.com
Fact