Both ZnO 30 and ZnO 40 display diffraction peaks characteristics of
zincite [26], at the angular values of 31.8[degrees], 34.6[degrees], and 36.2[degrees].
The dominant phases identified by XRD analysis are
zincite, franklinite and magnetite.
In the oxidation zone,
zincite is widespread as brownish yellow earthy fillings.
Other associated minerals are: smithsonite,
zincite, greenockite and quartz.
Harter (1928), for instance, reported franklinite and
zincite from Butte.
Of course, interesting crystal growth may also happen accidentally, sometimes as a byproduct of industrial operations, as in the case of the artificial
zincite crystals from Poland which appeared on the mineral market in the early 1990's (Robinson and King, 1991; Cooper, 1993).
The following standards were used: sanidine (K K[alpha]), cuprite (Cu K[alpha]), diopside (Ca K[alpha]), nichromite (Ni K[alpha]),
zincite (Zn K[alpha]), synthetic [Cd.sub.5][([PO.sub.4].sub.3](OH) (Cd L[alpha]), gehlenite (Al K[alpha]), synthetic V[P.sub.2][O.sub.7] (V K[alpha]), apatite (P K[alpha]) and phlogopite (F K[alpha]).
183, Munich 81735), where the specialty item was man-made
zincite. Next to that came an offering of colored alabaster nightlights; then began a group of Moroccan dealers and meteorite sellers.
In the first half of the 19th century, to the extent that Franklin and Sterling Hill were thought of as zinc mines, the most avidly sought of their ore species was the bright red
zincite (ZnO) that was often found as large masses and lenses in black franklinite, particularly at Sterling Hill.