Onyx vs Tourmaline
オニキスとトルマリンはどちらも人気の黒色系宝石です。トルマリンは硬度と輝きで優れ、オニキスは独特な個性が魅力です。
| Property | Onyx | Tourmaline |
|---|---|---|
| Category | Semi-Precious Gems | Semi-Precious Gems |
| Primary Color | black | various |
| Mohs Hardness | 6.5–7.0 | 7.0–7.5 |
| Specific Gravity | 2.55 | 2.85 |
| Refractive Index | 1.53 | 1.614 |
| Crystal System | Trigonal | Trigonal |
| Luster | — | Vitreous |
| Chemical Formula | — | — |
| Price Tier | Moderate ($50-500/ct) | Moderate ($50-500/ct) |
| Daily Wear | いいえ | はい |
Key Differences
- ◆ {'gem_a': '6.5', 'gem_b': '7.0', 'property': 'Hardness (Mohs)'}
- ◆ {'gem_a': 'Trigonal', 'gem_b': 'Trigonal', 'property': 'Crystal System'}
- ◆ {'gem_a': '2.55', 'gem_b': '2.85', 'property': 'Specific Gravity'}
- ◆ {'gem_a': '1.53', 'gem_b': '1.614', 'property': 'Refractive Index'}
- ◆ {'gem_a': 'N/A', 'gem_b': 'Vitreous', 'property': 'Luster'}
- ◆ {'gem_a': 'moderate', 'gem_b': 'moderate', 'property': 'Price Range'}
- ◆ {'gem_a': 'No', 'gem_b': 'Yes', 'property': 'Daily Wear'}
When to choose Onyx
独特な色彩と個性を求める方にはオニキスがお勧めです。特別な場面のジュエリーに向いています。
When to choose Tourmaline
傷つきにくさとより高い輝きを求める方にはトルマリンがお勧めです。婚約指輪や日常使いに最適です。
Frequently Asked Questions
Which is harder, Onyx or Tourmaline?
Tourmaline is harder at 7.0-7.5 on the Mohs scale, compared to Onyx at 6.5-7.0. This makes Tourmaline more resistant to scratching. Tourmaline is suitable for daily wear, while onyx requires more careful handling and is not ideal for daily wear.
Is Onyx more expensive than Tourmaline?
Onyx and Tourmaline are in a similar price range, both classified as moderately priced ($50-500/ct). Onyx typically ranges moderately priced ($50-500/ct), while Tourmaline ranges moderately priced ($50-500/ct).
Should I choose Onyx or Tourmaline for an engagement ring?
For an engagement ring, Tourmaline is the stronger choice with a durability rating of 7/10. At 7.0-7.5 Mohs hardness, it can withstand daily wear well. Onyx (6.5-7.0 Mohs) is softer and more prone to scratching with everyday use, making it better suited for occasional-wear jewelry.
How can I tell Onyx and Tourmaline apart?
There are several visual cues: Onyx typically appears black while Tourmaline is various; Tourmaline (RI 1.614-1.666) shows more brilliance than Onyx (RI 1.53-1.543). A gemologist can confirm identification using refractive index testing.
Why do Onyx and Tourmaline look similar?
Onyx and Tourmaline look similar because both can show overlapping colors — Onyx is black and Tourmaline is various.