First Australian diamond found in situ

by Roy Price
(Alice Springs)

In May 1977 I was recruited by Maureen Muggeridge to work for CRA Explorations on their diamond exploration program in the Kimberley. Because I had had previous experience as a field hand (with Planet Resources NL) I was selected to be offsider and driver to the then 53 year old senior geologist Frank Hughes.

On one occasion in June 1977 I accompanied Frank on a trip to Ellendale Station to do some reconnaissance prospecting. On day two we inspected a large depression in the landscape where thick rusty-coloured grass grew. The depression was actually the top of a large kimberlite pipe about 500m in diameter.

Later in the morning Frank directed me to take soil samples from between the striations of some nearby kimberlite outcrop. We washed the gravel in a gold pan with some water and when all the dirt had been removed and only the heavier material remained, Frank picked up what looked like a piece of graphite from a "lead" pencil. He looked at it with his loupe and said, "I think we've got one", wrapped it up in a piece of note paper and said nothing more about it for the rest of the day. When we got back to the office in Derby Frank put the rock under the microscope and sure enough it was most definitely a diamond.

I later found out that it was the first diamond in Australia found "in situ" - in the kimberlite (the rock type in which diamonds are deposited). Other diamonds and indicator minerals had been previously discovered in soil samples and creeks but this apparently was the first time in Australia that a diamond was found "in situ" - in the source rock.

I believe the attached photo is the diamond I saw under the microscope that day - not very pretty, burnt looking, scarred, but a diamond nonetheless.

So, I won't claim that it was I who found the diamond (I wouldn't have recognised it for what it was anyway) but I will claim I was there on the day.