soft-spoken adjective. âº usually âspeaking in a âquiet âvoice: a soft-spoken, âunderstated âstyle. (Definition of soft-spoken from the Cambridge Academic Content Dictionary Â© Cambridge University Press).
The laser drilling process involves the use of an infrared laser (of surgical grade at a wavelength about 1064 nm) to bore very fine holes (less than 0.2 millimeters or 0.005 inches in diameter) into a diamond to create a route of access to a black carbon crystal inclusion.
Alluvial diamond mining is the term used to describe the process through which diamonds are recovered from such deposits of sand, gravel and clay. Large concentrations of alluvial diamond deposits are mined on an industrial basis.