Identifying natural rough diamonds at Naturalmark Lab requires a systematic approach using both visual inspection and advanced analytical techniques.
Cleaning: Clean the rough diamond thoroughly to remove dirt and debris using ultrasonic or steam cleaning.
Visual Inspection: Use a 10x loupe or microscope to inspect the crystal shape, surface features, and inclusions.
Documentation: Record the size, shape, color, and any noticeable features.
Crystal Habit: Check for common diamond crystal forms such as octahedrons, dodecahedrons, or cubes.
Surface Features: Look for Triangular growth patterns (trigons) on the surface, Natural etchings or dissolution marks and distinctive grain lines or striations.
Transparency and Luster: Natural rough diamonds typically exhibit a greasy or adamantine luster.
Hardness Test: Scratch the sample using a corundum (hardness of 9) to verify diamond's hardness (10 on the Mohs scale).
Refractive Index (RI) Test: Use a refractometer to check the RI (diamond: 2.42).
Polariscope Test: Confirm singly refractive nature (diamonds are singly refractive, while many simulants are doubly refractive).
UV Fluorescence: Examine under short-wave and long-wave UV light for fluorescence patterns. Natural diamonds may show blue, yellow, or green fluorescence.
Raman Spectroscopy: Identifies carbon structure; diamonds exhibit a characteristic peak at around 1332 cm⁻¹.
Fourier-Transform Infrared Spectroscopy (FTIR): Detects impurities and distinguishes between natural and synthetic diamonds.
Photoluminescence (PL) Spectroscopy: Helps identify treatments and synthetic origins
5.Identification of Inclusions and Internal Characteristics
Microscopic Examination: Observe natural inclusions like mineral crystals, growth lines, and clouds.
Comparison with Database: We match results with reference data from gemological databases.
Expert Verification: We have trained gemologists and certified expert verify the findings.
Report Generation: After identifying the stone/stones, we generate a mini report with findings, methods used in rare cases and remarks.
Lets walk you through the report issued by Naturalmark.
Report : It carries a unique report number, an alpha numeric value for that rough diamond screened at Naturalmark Lab and is also used by the customer to check its authenticity by putting in the verify report section of our website.
Description : This tells whether the rough stones are of Natural or synthetic origin and whether the stones are treated or not and the type of treatment (HPHT)
Laser Engraving : A lot of stones are brought to Naturalmark Lab for identification and if they have a unique mark/laser cut on it, we mention it in the report issued.
Remarks : Any additional information required will be mentioned in the remarks section
Date : Gives the date in DDMMYY format on which Screening was done.
