Quartz and datolite
, two of the earliest minerals to form, are the main constituents inside cavities at the bottom of zone 4 (the lowermost of the four zones).
In the higher-temperature environment quartz deposition declined markedly as other elements, mainly calcium, aluminum and boron, united with silica to form prehnite, datolite
and other silicates.
As far as is known, only one report of crystal twinning in datolite
is found in the literature.
The geochemically associated non-zeolite minerals prehnite, datolite
and the apophyllite series were also noted at a number of localities.
Pezzotta describes the best specimens there (not only orthoclase, but also quartz, fluorite, datolite
, babingtonite etc.).
Fengjiashan Hubei amethyst, apophyllite, braunite, calcite, chalcopyrite, datolite
, hubeite, ilvaite, inesite, japanese twins, pyrite, stilbite/stellarite, wollastonite Fenglin Jiangxi chalcocite Fengsandong Hubei amethyst, bornite, apophyllite, chalcopyrite, datolite
, inesite, molybdenite, pyrite, parsettensite, stilbite Fushan Hebei vesuvianite, hematite Fushun Liaoning amber Fuyun Xinjiang, aquamarine, fluorite, garnet, hiddennite, Uygur A.R.
This quarry is best known for its outstanding datolite
and (rarely) babingtonite specimens, but these new white, translucent scalenohedrons and compound scalenohedrons of calcite, reaching 10 cm, are no poor sisters either.
(1965) The accessory minerals from Predazzo granite (North Italy), Part III (datolite
, gadolinite, hellandite, ancylite, synchisite, uraninite).
Also in the case were a huge 4.8-cm anatase crystal and a 10-cm plate of gemmy yellow datolite
along with a matching faceted datolite
For the mineral collector there was plenty more to choose from, including fine green datolite
from Charcas, Mexico.
At Wessels mine, ruizite is found with quartz, datolite
, pectolite, otientite, inesite and apophyllite (Wilson and Dunn, 1978).