Figure 1 shows the melting points of 2FeO*Si[O.sub.2] (fayalite) and 2MnO-Si[O.sub.2] (
tephroite) to be 2223F (1217C) and 2453F (1345C), respectively.
Dominant primary manganese minerals include spessartine,
tephroite, rhodonite, pyroxmangite, neotocite, bementite, Mn-rich cummingtonite, rhodochrosite and Mn-rich apatite (Pires, 1977, 1983).
Associated minerals are: jacobsite, kutnohorite, barite,
tephroite and spessartine.
The braunite ore is relatively rich in veins and vugs containing good specimens of rhodonite, rhodochrosite,
tephroite, kutnahorite, pyroxmangite and barite.
Associated minerals are: rhodochrosite, friedelite, hubnerite, sphalerite, stilpnomelane, albite, barite, hausmannite,
tephroite, welinite and an unidentified manganese vanadate.
Standards used were almandine (Mg and Fe), apatite (Ca and P),
tephroite (Mn), titanite (Ti) and fluorian riebeckite (F).
Andradite (*)Acanthite Arsenopyrite Benavidesite Bournonite Bustamite Cerussite Enargite Ferroan
tephroite (*)Fluorite Friedelite Grossular Jamesonite Johannsenite Magnetite Manganaxinite Mangan-pyrosmalite Marcasite Miargyrite Orpiment Polybasite (*)Proustite (*)Pyrargyrite (*)Pyrite Realgar Rhodonite Siderite (*)Silver Stibnite Uchucchacuaite Wollastonite
The standards used were: for Na, albite; Si and Mg, enstatite; Al, kyanite; Ca, wollastonite; Mn,
tephroite; Fe, fayalite; Th, Th[O.sub.2]; and U, U[O.sub.2].
The standards used were Marjalahti olivine for Mg, kyanite for Al, synthetic fayalite for Fe, and synthetic
tephroite for Mn.