Acquisition of the month: Japanese twin quartz

Japanse tweeling kwarts in hand

I recently added a fine specimen of a Japanese-law quartz twin to my collection from the Ambolo Quartz Mine in Madagascar. This crystallographic peculiarity is formed by two quartz crystals fusing together as contact twins at an angle of exactly 84°33′. What makes these twins so unique is that the two crystals remain individually identifiable, which is rare for quartz twins.

Most common forms of twin growth in quartz, in the first two examples the twins are fused into 1 crystal, but in Japanese twins the two crystals remain individually recognizable
Japanese twin quartz (53 mm wide, 8 mm thick; 38 g) with hematite inclusions,
Ambolo quartz mine, Marososona, Antsirabe II District, Vakinankaratra, Madagascar.

In a Japanese twin, two of the prism faces (sides of the prism) of both crystals are parallel, usually resulting in a distinctive V-shape or, as in my specimen, a heart-shaped silhouette. Often these twins look flatter and may also appear almost square or slightly asymmetrical, but the typical V often remains clearly visible, as do the 6 faces that form the point in quartz. My specimen, with its soft pink hue due to hematite inclusions, is a beautiful example of this rare growth form.

quartz Japanese twins 2

Want to know more about growth forms of quartz, such as Japanese twins? In my online mini-course on growth forms of quartz you will discover how these phenomena occur and learn to recognize them better. A must for every lover of quartz crystals!

Mini-Course-Growing-Forms-of-Quartz

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