Eudialyte
In 1817, a brown mineral was discovered in Greenland, but it was initially misidentified as garnet. Two years later, vibrant red specimens were found on the Kola Peninsula in Russia; today, almost all specimens circulating as jewelry with a known origin come from Russia.
A mineral derived from alkaline plutonic rocks, known for its striking bright red color
Basic Information
| English Name | Eudialyte |
|---|---|
| Japanese Name | Yudiaru-seki |
| Chemical Formula | (Na,Ca)5(Ca,Ce,Sr)2FeMnZrZn3[(O,OH)2|Si3O9]2[Si4O12]・SiO4・5H2O |
| Crystal System | Hexagonal |
| Hardness | 5–5.5 |
| Specific Gravity | 2.9 |
| Transparency | — |
Characteristics & Variations
- Occurrence: Found in pegmatites of alkaline plutonic rocks such as nepheline syenite.
- Associated Minerals: Nepheline, aegirine, white albite, and pale yellow apatite.
- Variety (Eucolite): A subspecies rich in Fe, Mn, and Ca, exhibiting a stronger brown tint. Found in the Langesundsfjord of Norway.
- Trade Names: "Lapland Ruby" (thought to be derived from the name "blood of the Laplanders").
Treatments, Similar Stones & Precautions
Treatments: Infused with oil or wax to enhance the polishing effect. Sometimes impregnated with synthetic resin. Raw stones with significant white areas may be dyed with red pigment.
Similar Stones: The bright red color can resemble ruby or red spinel, while brown specimens may resemble garnet. However, it can be distinguished from garnet by the fact that it does not fluoresce red under UV light and it decomposes easily in hydrochloric acid (HCl).
Precautions: It decomposes easily in dilute acids and also dissolves readily in alcohol. Avoid using anything other than distilled water for cleaning. Since sweat is weakly acidic, poor care can damage the surface.
Note: This is a "highly delicate stone" that is sensitive to acids and alcohol. Unless you establish a strict maintenance routine, its appearance will deteriorate in a short period of time.