REPORTED DIAMOND FIND.

New Zealand Herald, Volume LXVII, Issue 20760, 31 December 1930, Page 12

REPORTED DIAMOND FIND.

OPINION OF A GEOLOGIST

THE PROPERTIES OF ZIRCONS

[BY TELEGRAPH. —OWN CORRESPONDENT.] \VELLINGTON, Tuesday.

In view of the recent report that somewhero in the North Island diamonds of tho blue-white , variety had been discovered by R. McFarlane, tho posibility of diamonds being found in Now Zealand was to-day referred to a leading geologist. " From a geological point of view," ho said, " thero would seem to lie 110 reason against diamonds being in the country, but I do not think that I 01 any other geologist would affirm that it is very likely. It. is not the first time by any means that a supposed diamond field has been located. Blue clay of tho kind so well-known in the diamondiferous areas in South Africa has been found, and in it, sparkling gems have been seen, but unfortunately they have not been true diamonds. In fact no trace of a true diamond has ever been found in New Zealand.

"What has been found before and has given rise, to falsified iiopes, and what has probably been found this time, is zircon, which is not a diamond. HowOver, I do not want to throw cold water on Major McFariano's venture, especially as I have not seen the stones, and without seeing them [ naturally cannot say whether they are real diamonds or Dot. In the Henderson district and in some other areas zircons are fairly plentiful and can bo seen sparkling in tho sunlight, especially after rain."

Zircon is a mineral composed of zirconium silicate, and is sometimes used as a gem stono. When found it is rarely colourless, being usually brown or red, but at times it has other colours, blue, orango, yellow or green, 'and msy even be particoloured or zoned. The common zircon is opaque, but tho gem stone is transparent. Tho effect of heat on zircon is remarkable. The stone, when exposed to high temperatures, changes or loses colour, but. this is attended by a distinct gain in brilliance. Tho Matura diamonds of Ceylon are zircons artificially decoloured.

The zitcon gem stone is usually known as a "noble ' or "precious zircon." The red and orange varieties are' called "hyacinth" and "jacinth" respectively, other coloured varieties going by the name of "jargons."