| Haiweeite | |
| Category: | Nesosilicate |
| Formula: | Ca[(UO<sub>2</sub>)<sub>2</sub>Si<sub>5</sub>O<sub>12</sub>(OH)<sub>2</sub>]·3(H2O) |
| Imasymbol: | Hwe[1] |
| Strunz: | 9.AK.25 |
| Dana: | 53.3.2.2 |
| System: | Orthorhombic |
| Class: | Dipyramidal (mmm) |
| Symmetry: | Orthorhombic H-M symbol: (2/m 2/m 2/m) Space group: Pbcn |
| Other: | Radioactive |
Haiweeite is a mineral of uranium and has the chemical formula: Ca[(UO<sub>2</sub>)<sub>2</sub>Si<sub>5</sub>O<sub>12</sub>(OH)<sub>2</sub>]·3(H2O). It is a secondary mineral of uranium, a product of oxidation. It has a greenish yellow color. It has a Mohs hardness of about 3.5 and is fluorescent under UV light.
It was named after the Haiwee Reservoir, Inyo County, California, US, where it was first found.