Simulants and Practical Identification

Learning Objectives

• Explain why material identification comes before any natural-versus-laboratory-grown conclusion.
• Distinguish simulants from laboratory-grown diamond without overreading a visual sign or handheld tester.
• Apply a staged identification workflow and recognize when laboratory escalation is required.

Core

The first question is not “Is it natural?” but What is the material? Only after diamond has been established does natural versus laboratory-grown origin become the next question.

Moissanite, cubic zirconia, and other simulants can imitate diamond convincingly under some conditions. A single visual feature or inexpensive tester therefore should not carry more evidentiary weight than the method actually supports.

A laboratory-grown diamond is not a simulant. It is diamond material with a different growth history.

Apply

Begin by documenting the object and its condition, then use observations and tests appropriate to the sample. A thermal or combination handheld tester can be useful for quickly separating some simulants, but its result depends on device design, contact, size, setting, temperature, and validated scope. A “diamond” indication from a basic tester does not resolve natural versus laboratory-grown origin.

Likewise, a REFER result on a screening instrument is not a verdict of “synthetic.” It means the workflow must continue. Optical behavior, microscopy, electrical conductivity where relevant, and other observations can refine the question, but inconsistent or origin-sensitive results belong in laboratory analysis.

Mounted jewelry adds limitations because metal can restrict access and measurements. Small melee requires a different workflow from a larger loose stone, while a multi-stone item may require population-level screening before any individual-stone conclusion.

Professional identification is therefore not a collection of tricks. It is a decision tree with explicit escalation points.

Check Your Understanding

• Have I separated simulant identification from natural/LGD origin determination?
• Am I using a handheld tester only within the device’s validated scope?
• Do I understand that an ordinary diamond tester generally does not resolve natural versus laboratory-grown origin?
• Do I escalate a REFER result instead of treating it as “synthetic”?
• Have I adapted the workflow to loose, mounted, melee, or rough material?

Conclusion Boundary

Escalate when basic screening or microscopy does not resolve natural/laboratory-grown origin, growth method, or treatment status. For treated or potentially treated material, also escalate before heat, chemicals, steam, ultrasonic cleaning, or other service when stability and disclosure are uncertain.

Common Mistakes

“If it passes a diamond tester, it is natural.”
No. At most, the test may have confirmed a physical response compatible with diamond.

“Laboratory-grown diamond is a simulant.”
No. It is diamond material with a different origin.

“Moissanite is always obvious to the naked eye.”
No. Reliable identification requires appropriate methods and conditions.

“One negative test ends the identification.”
No. A professional workflow includes exception and referral paths.

Remember

Identification is hierarchical: material → diamond or simulant → natural/LGD origin → treatment. Do not skip a level.

Sources

• Handbook: HOK-DIA-HANDBOOK-CH-021
• The Book: HOK-DIA-BOOK-CH-064
• The Book: HOK-DIA-BOOK-CH-065
• The Book: HOK-DIA-BOOK-CH-066
• The Book: HOK-DIA-BOOK-CH-067