4 ms·
The second last photo labelled "Thames garnets tend to appear in specific spots along the riverbank, but those locations are carefully guarded among mudlarks. C
by dghughes 2y ago
The second last photo labelled "Thames garnets tend to appear in specific spots along the riverbank, but those locations are carefully guarded among mudlarks. Courtesy Jason Sandy" you can see a big one. It has what looks to be a five-sided facet that's reflecting light.
- adrian_b 2y agoThe natural garnet crystals have frequently the form of rhombic dodecahedra (i.e. with 12 rhombic faces disposed in the directions of the 12 edges of a cube). Such crystals may be eroded to more rounded forms, but some of the original plane faces may remain more or less intact. It is hard to be sure from the image, but the garnet below the title may be not artificial, but just an eroded natural garnet that originally was a rhombic dodecahedron. The same can be true for other faceted garnets. Only a more thorough examination can distinguish natural crystals from those that have been polished, so they have plane faces with other orientations than the faces of the natural garnet crystals.