Buttermilk Amber

[penguin]

hello, I've recently encountered a stone in jewelry referred to as "buttermilk amber". it's opaque and off-white, and I can't find any information on it through google searches. Anyone have any input on this?

[Auspex]

There is a surprising range of colors to be found in amber, and some fairly poetically descriptive names coined for them.

There is no other significance, outside the gem trade, to any of them.

[painshill]

The colour of amber depends a lot on the size and number of air bubbles it contains, which create an opacity that alters the perceived colour. When the bubbles are microscopically small and numerous, the conventional reddish or honey translucent appearance moves to opaque yellow, beige, cream, white and finally blue(!)

The International Amber Association controls the standards for certification and has a number of recommended designated terms, although “buttermilk” is not one of them. That’s just someone using marketing initiative to describe it in an attractive way.

“Opaque yellow amber” comes in all shades of yellow and beige and contains air bubbles up to about 25,000 per square millimeter (field of view). Beyond that it’s called “Opaque white amber” and comes in all shades of cream and off-white to chalky-white with air bubbles up to about 900,000 per square millimeter. At the extreme, it can be blue-tinged – but that’s largely an optical effect of the bubbles, not a true pigmentation.

In Dominican ambers blueness may also arise from trace impurities in combination with bubbles and the fluorescent hydrocarbon perylene has also been suggested as implicated in the colouration.

Edited October 4, 2013 by painshill

[penguin]

Thanks guys. I just wanted to make sure it was real amber and not some fake stone being passed off as a type of amber, i just had never seen amber like this. good to know it's real.

[Ash]

Sounds delicious, even if not a "proper" amber term.