catalogue of western australian meteorite collections

are not parts of a chemically gradational series. They represent thre'e distinct
chemical divisions separated by hiatuses, the hiatus between enstatite- and
oliyine-bronzite-chondrites being particularly marked.
Two further classes of chondrites are distinguished by Mason (196.2) who
has modified Prior's classification-these rare groups were formerly included by
Prior in the olivine-bronzite-chondrites. They are:-
(d) Olivine-pigeonite-chondrites (Cp)-consist of olivine Fa 32-40, nickeliron,
less than 6 %, pigeonite, 5 %, ollgoclase, 5-10 %, troilite, 5 %.
Specific, Gravity, 3 '4-3 ,6.
(e) Carbonaceous chondrites (C)-mayor may not contain olivine
chondrules in a dense carbonaceous groundmass composed of
serpentine or amorphous hydrated silicate. Specific Gravity 2·2-2' 9.
The Rose-Tschermak-Brezina system (op. cit:) made use of the following
distinctions in the case of each of the subdivisionsmineralogy
:
enstatite-, hypersthene-, and pronzite-chondrites (based on pyroxene
present)
C