What does J 12-13 mean in a diamond?

Answer 1

Most properly, your descriptors are the letter J, which refers to the diamond's colour, and I2- I3 (eye), which refers to its clarity.

On the scale of colourless diamonds, J fits into the range of slightly yellow; I2-I3 indicates two or three visible inclusions, or flaws in the stone.

You can buy a one carat round diamond with a similar grade today on Blue Nile and spend from US$2,300 to US$2,600. A similar carat weight stone with a less yellow colour and no flaws would be priced in the US$9,500 to US$15,700 range.

Answer 2

The grading for clarity for diamonds ranges from FL – flawless, IF – internally flawless, VVS1’2 – very very slightly included, VS1’2 – very slightly included and SI1, SI2 – slightly included. Clarity measures how clean a diamond is from inclusions. L1, L2 and L3 clarity means Inclusions are obvious under 10x magnification and may affect transparency and brilliance and I1 diamonds have inclusions that are almost always visible to the naked eye. In terms of color, diamonds are graded based on the following: D, E, F G, H, I, J, K, L and M, developed by the Gemological Institute of America ranging from colorless to light yellow. I-J diamonds are more common than the higher grades, they tend to be a great value.