Louderback, G. D. "Benitoite, Its Paragenesis and Mode of Occurrence."
University of California Publications.
Page 354
Lately some very good results have been obtained by the use of the emerald
cut which gives good color-value with but slight loss of brilliancy. A
number of the stones have also been cut en cabochon . This allows the use
of the less perfect material and also of that which varies considerably in
color in the same piece, containing perhaps with the deep blue certain areas
without color. The results have been quite satisfactory.
Name . The name of the mineral was taken from San Benito, the name of
the county in which the mine lies, of the river, at the headwaters of which
the deposit occurs, and of a nearby peak of the range. [11]
NEPTUNITE.
Crystallography.
Neptunite is an abundant and characteristic mineral of the deposit. Prior to
its discovery in California it had been reported only from Greenland. [12] In
the original benitoite material a small section of a prism without terminal
faces was suspected to be a new mineral and the name carlosite suggested
for it. Soon after the mine was visited satisfactory material was obtained and
its identity with neptunite recognized.
The forms observed at the San Benito locality are c (001),
b (O10),
a (100), m (110), s (111), o (111),
i (112), g (211), r (221), p (311).
* Crystals set with prism zone at p=90° 00² and angles
ø referred to a as 90° 00²
NOTES:
11 The correct and usual pronunciation of place names of Spanish origin
in California approximates the original Spanish pronunciation. In Benito the
accent is on the penultimate syllable aDd the i has the sound of i in
machine. In conformity with this the name of the mineral is properly to be
pronounced be-nï'-to-ite. Benito is a Spanish form of benedictus,
blessed.
12 Flink, Zeit. für Kryst., 23 (1894) pp. 344-367;
Nordenskiöld,
Geol. Fören. Förh., 16 (1894) p. 336; Wallenström,
ibid. 27 (1905) p. 149; Böggild Meddelelser om
Grönland, 33 (1907) pp. 95-120.
[ Images of the gem][
Articles][
Maps][
The mine]