Blue diffusion-treated sapphires are be- coming more prevalent than ever before. The diffusion technique, which involves the addition of color-causing chemicnls during heat trentment, results in a thin layer of color at the surface of colorless or light-colored sapphire.

Are diffused sapphires worth anything?

The price between each level of treatment can range from. The exceptionally expensive US$5,000 per carat for unheated natural sapphires. To US$1 per carat for the new treatment lattice-diffused sapphires which has now flooded the market today.

What does diffused mean in gemstones?

Coloured gemstones have undergone treatment for thousands of years. ... Diffusion is a technique whereby certain natural elements, those used in nature when colouring allochromatic gems, are placed on the surface of the gem during the heating process and the colour is diffused into the gem.