This is a one pieces Moissanite Gemstone, D Color Round RD 6.5mm 1 Carat VVS1, you can test with any diamond tester.
I also have moissanite with more size and shape selections, you can always find a fit your need, here is my other list: https://www.ebay.com/itm/265104896707
Gemstone Name :- Moissanite
Gemstone Size :- 6.5 mm ( 1 CT)
Gemstone Quantity :- One Pieces
Gemstone Cut :- Faceted Cut
Gemstone Shape :- Round Shapes
Gemstone Quality :-Good Quality
Gemstone Color :- White Color (D)
Gemstone Clarity :-Transparent
Gemstone Type :- Synthetic Gemstone
The weight table below is approximate only, and it's the equivalent weight to same size diamond, not the actual moissanite stone weight.