CPF poster: diamond screening and identification

Poster – “CPF technique on screening and ID of DIAMONDS – natural, lab-grown and post treated”

Authors: Randy Lightfoot and Branko Deljanin

Language: English

Introduction

This poster is designed for professionals who want to add more to their daily workflow. screening technique when working with diamonds. Method CPF (cross-polarized filters) offers a practical way to observe and interpret strain patterns in diamond and understand their connection to the origin and stresses during and after crystal growth.

Main advantages

• Practical screening tool: CPF is described as an affordable and relatively simple additional screening step.

• Focus on strain pattern interpretation: supports understanding of what voltage patterns show and why they are monitored.

• Relevance for different types of diamonds: poster works with the context of diamonds natural, lab-grown and post-treated.

• Durable design for operation: Double-sided lamination for longer life and easier surface maintenance.

Use

• Gemological laboratory/workshop: as a quick reference tool at the workplace for screening and documenting observations.

• Office/Team Training: for unification of terminology and interpretation (what CPF monitors, how to communicate about it within the identification process).

• Sales consultation: as a visual support for explaining why certain screening steps make sense and when it is appropriate to follow up with other methods.

Limitations

The poster serves as an educational and reference material; it does not, by itself, replace a complete identification procedure or laboratory conclusion.

Technical specifications

• Type: poster

• Dimension: 91 × 61 cm (35.8 × 24 in)

About the authors

Randy Lightfoot is a gemologist and appraiser specializing in microscopy, photomicrography and visual identification of inclusionsHe holds professional degrees and memberships in the field (including Certified Gemologist (AGS), Registered Gemologist Appraiser (ISG)) and also works as a lecturer in Branko Gems educational programs. 

Branko Deljanin is a recognized expert in the identification of natural, treated and synthetic diamonds and colored stones with extensive experience in North America. He is highly skilled in the use of traditional gemological tools as well as advanced spectrometers.