Comparison · Precious Stones
Alexandrite vs Ruby
Alexandrite and Ruby are easy to confuse because both are precious stones. Both sit near Mohs 8.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Below is a side-by-side comparison of their properties and the quick tests that separate them.
Key differences between Alexandrite and Ruby
- Both sit near Mohs 8.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- They overlap in red, but Alexandrite also comes in green and Ruby also comes in pink.
- Well-formed crystals give it away: Alexandrite is orthorhombic, Ruby is trigonal.
Alexandrite vs Ruby properties
| Property | Alexandrite | Ruby |
|---|---|---|
| Type | Precious Stones | Precious Stones |
| Mohs hardness | 8.5 | 9 |
| Luster | vitreous | adamantine |
| Streak | White | White |
| Transparency | transparent | transparent |
| Specific gravity | 3.7 | 4 |
| Crystal system | orthorhombic | trigonal |
| Common colors | Green in daylight, Red in incandescent light | Red, Pinkish Red, Purplish Red |
| Rarity | epic | rare |
| Typical specimen value | $5000–$70000+ | $1000–$100000+ |
Which is more valuable?
Alexandrite is usually the more valuable of the two: a typical collector specimen runs about $15000 against $10000 for Ruby, and premium Alexandrite can reach $70000 or more.
About Alexandrite
Alexandrite is a rare color-changing variety of chrysoberyl that appears green in daylight and red under incandescent light. It's one of the rarest gemstones.
About Ruby
Ruby is a red variety of corundum, the second hardest natural mineral. Its intense red color comes from chromium impurities.
Alexandrite vs Ruby FAQ
Is Alexandrite the same as Ruby?
No. Both are precious stones, but they are distinct species with different hardness, streak or luster. Both sit near Mohs 8.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Alexandrite from Ruby?
Both sit near Mohs 8.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. They overlap in red, but Alexandrite also comes in green and Ruby also comes in pink. Well-formed crystals give it away: Alexandrite is orthorhombic, Ruby is trigonal.
Which is harder, Alexandrite or Ruby?
Ruby is harder: Mohs 9 against Mohs 8.5 for Alexandrite.
Which is more valuable, Alexandrite or Ruby?
Alexandrite is usually the more valuable of the two: a typical collector specimen runs about $15000 against $10000 for Ruby, and premium Alexandrite can reach $70000 or more.
