The Unripe Gold — Geoffrey Jenkins

The discovery of a major source of iridium near the diamond fields of South Africa was a deadly secret. For whoever controlled the supply of that rare metal so essential to strategic weapons development would have world power at his fingertips. But as newcomers gathered in the small mining town, Professor Reutemann, an East German scientist, found out that his 'unripe gold' was no secret-that the dangerous power might all too soon be turned against HIM...

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