[Boatanchors] materials new to me

[CLIVE COLLINS]

Good day gentlemen,
I have stumbled across a reference to a material that I have never heard of before and, while it is off topic, I would be glad of some idea as to what it is please.
There is an advert on the bay place that is numbered 250439283724 for some resistors that are said to be made from "stable carbon" and 'white carbon',
I have never heard of this, anybody know what it means please. If the details are to be believed then there is a big gap in my knowlege.
Regards

Clive GW3WEQ