A whole-stone grade of high quality natural drill diamond with stones that are octahedral or dodecahedral in shape with no internal fissures or cracks. Recommended for use when drilling igneous and harder sedimentary formations.
A processed grade of medium quality natural drill diamond with stones that are approximately spherical in shape. Their surface texture may exhibit some irregularities but are free from any internal fissures or cracks. Recommended for use when drilling sedimentary formations.
These stones are sometimes referred to as “black diamond”. They are an opaque grey/black coloured aggregate of diamond crystals, graphite and amorphous carbon. They naturally occur as relatively large, irregularly shaped crystalline structures that are mechanically split into angular shapes with desired particle sizes. Normally, individual carbonado crystals are sized in the range of 10 stones per carat (SPC) or larger. Bits that are set with carbonado crystals are particularly well suited for use in drilling softer formations or hard/soft blended formations such as Serpentine.