Rockwoodin

Rockwoodin is a fictional mineral species introduced for illustrative purposes in geology and mineralogy. It is described as a hydrated aluminosilicate with a layered crystal structure, commonly forming tabular to prismatic crystals. Color ranges from pale olive-green to brown, with a vitreous to pearly luster.

Occurrence and formation: In the imagined setting, Rockwoodin develops during regional metamorphism of aluminous sedimentary rocks in the fictional Rockwood Range. It is found in small veinlets within metamorphic rocks and is typically associated with garnet, quartz, muscovite, and epidote.

Properties and identification: Rockwoodin has a Mohs hardness around 6, a specific gravity in the low 3s, and a streak that is white to pale gray. It crystallizes in a monoclinic system, forming platy or prismatic crystals. Analyses describe its composition as primarily aluminum and silicon with calcium and sodium, and trace iron or magnesium.

Uses and significance: In teaching and reference works, Rockwoodin serves as an example of how mineral properties are documented, including crystal habit, optical properties, and paragenesis. It has no commercial mining value in the fictional setting, but is valued by collectors and educators for its aesthetic crystals.