Kimberley Diamond Co NL has discovered the first pink diamond at its Ellendale project in Western Australia.

The rare diamond weighs in at 1.58 carats and has an indicative value of at least $US20,000 per carat in the rough.

When polished, its value increases to $US30,000 to $US40,000 per carat.

Kimberley Diamond has also discovered a 10 carat white diamond and a three carat octahedral fancy yellow stone.

"The upper end of the diamond market, which tended to be insulated against last years market fluctuations, continues to perform particularly strongly with record demand for better quality larger and specialty diamonds," it said.

"This is strategically important for Kimberley, given that Ellendale produces a significant proportion of the world's fancy yellow diamonds."

Industry projections are for a positive long-term outlook, with diamond prices expected to keep rising.

Global demand for diamonds is set to exceed supply over the next 10 years, or until new deposits are found and reach the production stage.