Rutilated Quartz

Hardness: 7 on the Mohs scale (for quartz); Luster: Vitreous; Color: Clear, cloudy, smoky, or milky quartz with metallic (usually golden, reddish, or silvery) rutile needles; Crystal structure: Trigonal (quartz) with tetragonal (rutile) inclusions; Cleavage: None (quartz); Specific Gravity: 2.65 for quartz, rutile inclusions slightly increase it.

Rutilated Quartz forms when needles of rutile (a mineral composed of titanium dioxide) grow within quartz crystals during their formation. This typically occurs in high-temperature and high-pressure metamorphic or igneous environments, particularly in pegmatites. The rutile inclusions are formed from titanium present in the environment precipitating out as needle-like crystals within the growing quartz. The geological age varies depending on the specific deposit, often found in ancient shield areas and active volcanic regions.

Rutilated Quartz is highly prized in jewelry for its unique aesthetic appeal, often cut into cabochons, beads (as seen in the image), and faceted stones for rings, pendants, and earrings. It is also a popular collectible mineral specimen. Metaphysically, it is believed to amplify energy and thought, and is associated with spiritual growth.

The word 'rutile' comes from the Latin 'rutilus', meaning red, referring to the deep red color observed in some rutiles when viewed by transmitted light. Rutilated Quartz is sometimes called 'Angel Hair Quartz' due to the fine, delicate appearance of the rutile needles. The aesthetic quality of Rutilated Quartz depends on the density, color, and distribution of the rutile needles within the quartz.

In the field, Rutilated Quartz can be identified by its characteristic transparent to translucent quartz host material containing distinct, often metallic, needle-like inclusions. The inclusions can be fine and sparse or dense and intricate, appearing as golden, reddish, or silvery threads. It is commonly found in Brazil (Minas Gerais), Australia, Madagascar, Russia, and the United States (North Carolina). When identifying, look for the 'threads' or 'hairs' within clear quartz. Be cautious of imitations, as synthetic versions can sometimes be produced.