In the early days ('70s) of the diamond impregnated scaives (DIS), the easiest way to make

a meaningful matrix was with cobalt. It has all the right physical properties to get a

hard and well cutting scaife. 

But after some years polishers in the Antwerp area started complaining about lung


This is were the Belgian manufacturers of DIS were forced to produce their scaives

without cobalt. WITTOCX NV took a leading roll, and came up with

the first cobalt-free diamond scaife. The present scaife has had a 10 years of

continuous development  and can now be regarded as the best scaife on the market.

(to know more about our current DIS, click here)

The problem of cobalt containing scaives now also has struck the Indian market. In order

to ensure no workers get lung disease we advise to buy only cobalt free diamonds


The difference between these two DIS can be detected due to a chemical reaction

 (cobalt+Sulfuric Acid-H2SO4-95%)

of cobalt with an acid. This examination will also result in the diamond layer being

 somewhat destructed. 


Pictures (click to enlarge):

cobalt containing + acid

cobcontaining.jpg (98273 bytes)cobcontcloseup.jpg (166337 bytes)


cobalt-free + acid

cobaltfree.jpg (155250 bytes)closeupcobaltfree.jpg (359398 bytes)