Lulzacite is a strontium-containing phosphate mineral with the chemical formula Sr2Fe2+(Fe2+, Mg)2Al4(PO4)4(OH)10. It is a triclinic-pinacoidal mineral containing aluminum, hydrogen, iron, magnesium, oxygen, phosphorus, and strontium. It occurs there as a dark grey to green granular aggregates within an Ordovician quartzite.
It was named for the discoverer of the mineral, Y. Lulzac. Found only at the type locality at the Bois-de-la-Roche quarry in Pays de Loire in France.
- Category: Phosphate minerals
- Formula: Sr2Fe2+(Fe2+,Mg)2Al4(PO4)4(OH)10
- Crystal system: Triclinic
- Crystal class: Pinacoidal (1)
- Color: Grayish-green to yellowish-green.
Lulzacite is a very rare, one-locality, strontium – Fe-Al phosphate found with siderite. The Lulzacite is the glassy bluish grey, compact and massive areas on this specimen.
- Crystal habit: Anhedral aggregates; rarely small euhedral crystals
- Cleavage: None
- Mohs scale hardness: 5.5–6
- Luster: Vitreous
- Diaphaneity: Transparent–translucent
- Specific gravity: 3.55
- Optical properties: Biaxial (−)
It occurs in veins of quartz and siderite, with pyrite, apatite, and goyazite.
The mineral was first described in 2000 from quartzite deposits (47°42′50″N 1°29′20″W) at Saint-Aubin-des-Châteaux, Loire-Atlantique, France, and is named after Y. Lulzac, a French geologist who discovered the mineral. In this deposit, lulzacite occurs within quartz and siderite veinlets at quartzite–limestone contacts. Other minerals found in the veinlets include apatite, goyazite, and pyrite.