Ruby vs Spinel

Comparing Ruby and Spinel — two popular gemstones that share a similar color palette. On the Mohs scale, Ruby rates 9.0 and Spinel rates 8.0. In terms of price, Ruby falls in the investment-grade range and Spinel in the fine/premium range.

Property Ruby Spinel
Category Precious Gems Semi-Precious Gems
Primary Color red various
Mohs Hardness 9.0 8.0
Specific Gravity 3.97 3.54
Refractive Index 1.762 1.71
Crystal System Trigonal Isometric
Luster Vitreous
Chemical Formula
Price Tier Investment ($5,000+/ct) Fine ($500-5,000/ct)
Daily Wear Yes Yes

Key Differences

  • {'gem_a': '9.0', 'gem_b': '8.0', 'property': 'Hardness (Mohs)'}
  • {'gem_a': 'Trigonal', 'gem_b': 'Isometric', 'property': 'Crystal System'}
  • {'gem_a': '3.97', 'gem_b': '3.54', 'property': 'Specific Gravity'}
  • {'gem_a': '1.762', 'gem_b': '1.71', 'property': 'Refractive Index'}
  • {'gem_a': 'N/A', 'gem_b': 'Vitreous', 'property': 'Luster'}
  • {'gem_a': 'investment', 'gem_b': 'fine', 'property': 'Price Range'}
  • {'gem_a': 'Yes', 'gem_b': 'Yes', 'property': 'Daily Wear'}

When to choose Ruby

Choose Ruby when you want superior hardness and scratch resistance, higher brilliance and light performance, premium quality and rarity, and its significance as the modern July birthstone. It's ideal for engagement rings and everyday jewelry.

When to choose Spinel

Choose Spinel when you want a more budget-friendly price point. It's ideal for engagement rings and everyday jewelry.

Frequently Asked Questions

Which is harder, Ruby or Spinel?
Ruby is harder at 9.0 on the Mohs scale, compared to Spinel at 8.0. This makes Ruby more resistant to scratching. Ruby is suitable for daily wear, while spinel is suitable for daily wear.
Is Ruby more expensive than Spinel?
Yes, Ruby is generally more expensive. Ruby is classified as investment-grade ($5,000+/ct) with prices around investment-grade ($5,000+/ct), while Spinel is fine/premium ($500-5,000/ct) at fine/premium ($500-5,000/ct).
Should I choose Ruby or Spinel for an engagement ring?
Both Ruby and Spinel can work for engagement rings since both are suitable for daily wear. Ruby has a slight edge with a durability rating of 10/10 with 9.0 Mohs hardness, while Spinel comes in at 8.0 Mohs. Your choice may come down to color preference and budget.
How can I tell Ruby and Spinel apart?
There are several visual cues: Ruby typically appears red while Spinel is various; Ruby (RI 1.762-1.778) shows more brilliance than Spinel (RI 1.71-1.735); they have different crystal systems — Ruby is Trigonal and Spinel is Isometric. A gemologist can confirm identification using refractive index testing.
Why do Ruby and Spinel look similar?
Ruby and Spinel look similar because both can show overlapping colors — Ruby is red and Spinel is various.

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