Moissanite

All Moissanite stones are manufactured in the same Charles & Colvard laboratory and, contrary to some advertising I've seen on the internet, a jeweler cannot purchase either Moissanite rejects or Moissanite jewels that are said to be superior to other Moissanite stones. 

Moissanite is not separated into grades because Charles & Colvard has set specifications that each stone must meet before being released to distributors. Those specifications are comparable to diamonds which have been graded VSI (Very Slightly Included - Minor inclusions difficult to locate at 10x).  

Moissanite has no real inclusions...rather it has white, needle like structures which cannot be seen without 10x magnification and even then, they are very difficult to see. In addition, since Moissanite has no natural fractures, it is considered sturdier than diamond because it has no fractures that might crack if it is subjected to an impact of some kind. 

*Moissanite is lighter in weight than diamond.  An 8 mm round diamond, which has been cut to diamond industry specifications, weighs approximately 2 carats.  An 8 mm round Moissanite – identical to the diamond in every way, will weigh 1.63 carats.  Both stones are identical in size and shape but the diamond will weigh more than the Moissanite.  

Also, Moissanite is very very hard -- second only to diamond.  Sapphire, used in industry because of its hardness, is not as hard as Moissanite.  This is the reason that Moissanite maintains its clarity and sparkle beyond a lifetime. The only other gemstone that can scratch Moissanite is another Moissanite or a diamond -- so the optical characteristics of  Moissanite are comparable or superior to diamond (sparkles more).  

However, you need to know that Moissanite cannot compare in color to a colorless diamond. Completely colorless diamonds are very rare and very expensive. Moissanite's color can be found in the G through J diamond grading color scale.  You will not find a D diamond color graded Moissanite stone. 

Moissanite also comes in a dark green and a light green.