Some five or six years before they had some experience in cleaving the ‘Excelsior’, a rough diamond weighing more than nine hundred carat. This stone belonged for the biggest part to the London Rough Syndicate, today known as the Diamond Trading Company (part of DeBeers) The Asschers also had a substantial interest in the stone.
They sought comparisons with the large stones. ‘The Jonker’ a stone belonging to H Winston in the United States weighed over seven hundred carats, the “Woyie’ belonged to Chester Beaty. manufactured by Briefel and Lemur in London also weighed in at seven hundred carats.
Well, the Excelsior had kept the old man Asscher and Joseph busy for weeks, it was murder! The first groove took nearly two days to cut. On a Wednesday afternoon,I was free from the school and I witnessed the first attempt to cleave the stone. It split beautifully in two, and both surfaces were as smooth as a mirror, the pieces were then sent to London, there to be processed further.
All the polished stones (from the Excelsior) became blue and white, as beautiful as can be, but two pear shapes, each weighing twenty-five carats, turned brown, in my fifty year career I have rarely witnessed such a thing.
Back to business, Joseph gave me the following tasks.
- Create and manufacture an extra sturdy cleaving table.
- Construct a cleavers box with a sliding side wall, which would drop this large stone to the required level so the sharp pieces of rough used to make the groove, would be at the right height.
- Fabricate cleaving sticks to hold this massive stone in different sizes.