Re: California USA vs. diamonds

Charles wrote:

On Tue, 28 Mar 2006 04:47:30 GMT, "« Paul »" <" « Paul
»"@houston.rr.com> wrote:

I recently viewed several maps showing diamond collecting areas in California.
Apparently diamonds have been found in most areas north of the Bay and east into
the Sierras. However, the literature made no mention of pipes.

Kopf, R. W., C. S. Hurlbut, and J. I. Koivula. 1990. Recent discoveries of large
diamonds in Trinity County, California. Gems & Gemology 26 (3): 212-19.

Does anyone know where I can find more literature / references?
An inter/intra library search turned up nothing.

Some mention in "Minerals of California" by H. Earl Pemberton. He
refers to J. Murdoch and Webb, 1966, pp 170-171. Minerals of
California. Calif div. Mines and Geol. bull 189, 559 pp.

Pemberton says :
"In California, diamonds have been found only in placer gravels and in
the black sands and concentrates of placer mines." ... "The diamonds
presumably have come from the basic igneous rocks from which the
serpentines of the gold regions have been derived."

Thanks! I'll find your reference.
.