Formula: CaCu(U6+O2)(PO4)2·4H2O
Hydrated normal uranyl phosphate
Crystal System: Monoclinic
Specific gravity: 3.71 calculated
Hardness: 3 to 3½
Streak: White
Colour: Apple-green, lime-green
Solubility: Readily soluble in dilute HCl and HN03.

Plutonic igneous environments

Ulrichite is a rare mineral, to date (March 2024) reported only from the type locality.


The type locality, the Lake Boga granite, Lake Boga, Swan Hill Rural City, Victoria, Australia, is a very large intrusion formed about 365 million years ago. The entire outcrop of the granite is overlain by sediments in places up to several hundred meters thick. The sole exposure into the granite is the Lake Boga quarry, where the sediment is only a few metres thick. The uppermost levels of the granite exhibit aplite veins, pods of pegmatite, and numerous miarolitic cavities, features that are characteristic of the uppermost levels of a granite magma intruded to shallow crustal levels (R&M 97.1.28-32).
Ulrichite occurs here typically as radiating sprays of apple-green to lime-green acicular crystals up to 1 mm long and 0.05 mm thick, and also as flat prisms. It occurs with turquoise and chalcosiderite in miarolitic cavities in pegmatoidal granite in the quarry. Other associated minerals include fluorapatite, libethenite, cyrilovite, torbernite and saléeite (AM 75.243).

Ulrichite from Lake Boga - Image

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