| Phoenicochroite | |
| Category: | Sulfate (chromate) mineral |
| Formula: | Pb2O(CrO4) |
| Imasymbol: | Phc[1] |
| Strunz: | 7.FB.05 |
| Dana: | 35.1.2.1 Anhydrous chromates |
| System: | Monoclinic |
| Class: | Prismatic (2/m) (same H-M symbol) |
| Symmetry: | C2/m |
| Unit Cell: | a = 14 Å, b = 5.67 Å, c = 7.13 Å; β = 115.22°; Z = 4 |
| Color: | Dark red, bright red |
| Habit: | Tabular crystals; thin coatings, and massive |
| Cleavage: | Perfect on |
| Tenacity: | Sectile |
| Luster: | Adamantine, resinous |
| Streak: | Brick-red |
| Diaphaneity: | Translucent |
| Gravity: | 5.75, 7.01 |
| Opticalprop: | Biaxial (+) |
| Refractive: | nα = 2.380, nβ = 2.440, nγ = 2.650 |
| Birefringence: | 0.270 (δ) |
| 2V: | 58° (measured) |
| Other: | Health risks: contains carcinogenic and mutagenic chromate ion |
| References: | [2] [3] [4] |
Phoenicochroite, also known as melanochroite, is a lead chromate mineral with formula Pb2OCrO4. It forms striking orange red crystals. It was first discovered in 1839 in Beryozovskoye deposit, Urals, Russia.[5] It is named from the Greek word φοίυικος for "deep red" and χρόα for "color", in allusion to its color.[5]