I didn't trust the system. As the waste was carried off my eyes
followed it. I was worried. How could they be so sure, day after day,
that no diamonds had slipped past in the tailings? And another thing;
what would happen nowadays to a big diamond, I asked, as for instance
the other half of the Cullinan, if by chance it turned up in the blue
ground and fell into that crusher?
It was evident that I had asked a rather awkward question. I learned that it is on record that one or two big stones have as
a matter of fact been destroyed in this manner. It is true that the
blue ground is carefully inspected throughout the process, from crusher
to crusher, down to the working size of Vs of an inch or less.
Men are stationed to inspect the conveyer belts that carry the gravel
along, and anyone who catches a big diamond in this manner is paid a
good bonus. Nevertheless a stone does slip past now and then and is
ruined. The tactful visitors learn not to lament this fact too
strenuously, for mining engineers in the diamond industry are rather
touchy on the subject of big stones. They resent the publicity
received by the giants. They take the side of the littler, unsung
diamonds, the gallant small things that are extracted in bulk and put
into ordinary engagement rings or factory tools, for on these the whole
trade depends today. It is unfair, say the engineers, to act as if
diamond mining were simply a matter of digging up a Cullinan once a
wouldn't keep a mine going steadily on the proceeds of the big
fellows," one of the men said to me indignantly. "You couldn't run this
industry on fancy stones. Where would we all be if we tried?"