The Where of Mineral Names: Windhoekite, Aris Quarry, Windhoek Rural, Khomas Region, Namibia.

Windhoekite, Graph HT <math display="inline" xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi mathvariant="normal">C</mi><msub><mrow><mi mathvariant="normal">a</mi></mrow><mn>2</mn></msub><mi mathvariant="normal">F</mi><msubsup><mrow><mi mathvariant="normal">e</mi></mrow><mrow><mn>2.67</mn></mrow><mrow><mn>3</mn><mo>+</mo></mrow></msubsup><mo stretchy="false">[</mo><mi mathvariant="normal">S</mi><msub><mrow><mi mathvariant="normal">i</mi></mrow><mn>8</mn></msub><msub><mrow><mi mathvariant="normal">O</mi></mrow><mrow><mn>20</mn></mrow></msub><mo stretchy="false">]</mo><msub><mrow><mrow><mo stretchy="false">(</mo><mi mathvariant="normal">O</mi><mi mathvariant="normal">H</mi><mo stretchy="false">)</mo></mrow></mrow><mn>4</mn></msub><mo>-</mo><mn>10</mn><msub><mrow><mi mathvariant="normal">H</mi></mrow><mn>2</mn></msub><mi mathvariant="normal">O</mi></mrow></math> ht , is a rare hydrated silicate of calcium and iron. Windhoekite, C a 2 F e 3 - x 3 + (S i 8 O 20) (O H) 4 - 10 H 2 O, a new palygorskite-group mineral from the Aris phonolite, Namibia. The palygorskite-group minerals (including windhoekite) are among the last to crystallize in the miarolitic cavities; Chukanov et al. ([2]) suggest the following general order of crystallization: microcline -> aegirine -> fluorapophyllite -> palygorskite-group minerals -> arisite. [Extracted from the article]