Menezesite

menezesite

clinohumite

ancylite-(Ce)

tochilinite

Images

Formula: Ba₃MgZr₄Nb₁₂O₄₂.12H₂O
Oxide, barium-, zirconium- and niobium- bearing mineral
Crystal System: Isometric
Specific gravity: 4.181 calculated
Hardness: 4
Streak: White
Colour: Reddish brown
Luminescence: No fluorescence under UV
RADIOACTIVE
Environments

Plutonic igneous environments
Carbonatites

Menezesite was approved in 2005 and to date (January 2023) has been reported only from the type locality.

Localities

At the type locality, the Jacupiranga Alkaline Complex, Cajati, São Paulo, Brazil, menezesite occurs as a vug mineral in the contact zone between dolomite carbonatite and jacupirangite. Associated minerals include dolomite, calcite, magnetite, clinohumite, phlogopite, ancylite-(Ce), strontianite, pyrite and tochilinite. The menezesite forms transparent, vitreous rhombododecahedra up to 1 mm, isolated or in aggregates.
Menezesite is the first naturally occurring heteropolyniobate discovered (AM 93.81-87).

Back to Minerals