TOPAZ
Topaz
Topaz
A gem available in blue, pink, colorless and other colors, extending well beyond the yellow traditionally associated with its name.
GEM PROFILE
Basic properties
- Mineral or material
- Topaz
- Main chemical composition
- Al₂SiO₄(F,OH)₂
- Crystal & structure
- Orthorhombic
Prismatic crystals are characteristic. Perfect cleavage in one direction requires care with impacts.
- Typical colors
- Colorless, blue, yellow, orange, pink and more
- Mohs hardness
- 8
A measure of scratch resistance, distinct from resistance to impact or breakage.
About hardness and durability - Representative sources
Examples of known sources. Determining the origin of an individual stone requires examination and comparison with reference material.
- Common cutting styles
- Rectangular step cuts, ovals, pears and other shapes.
Explore cutting styles
LOOK A LITTLE CLOSER
What to observe
Hardness 8 describes resistance to scratches. Because topaz has cleavage, this number does not indicate resistance to breakage from impact.
TREATMENT & CARE
Treatments & care
Treatments & identification
Irradiation combined with heating is widely used to produce blue colors. Coated topaz also exists.
Everyday care
Avoid impacts, ultrasonic or steam cleaning and sudden temperature changes. Wash gently with lukewarm water and mild detergent.
Cleaning depends on treatment, inclusions and mounting. If a stone's condition is unknown, ask your jeweler or a gem specialist before cleaning.
READING & REFERENCES
References
Public sources for learning about this gemstone's general properties.
- GIA · Gemological reference
- GIA · Care & Cleaning
- Handbook of Mineralogy · Mineral data (PDF)
- GIA · Gem sources and fundamentals
This dictionary provides general educational information. Values are representative and do not identify or grade an individual stone. Locality examples include historical deposits.
Sources checked: October 19, 2026