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GIA DIAMONDS AND DIAMOND GRADING
FINAL EXAM NEWEST 2025/2026 COMPLETE
ALL 180 QUESTIONS AND CORRECT ANSWERS
(VERIFIED ANSWERS) |ALREADY GRADED
A+||BRAND NEW VERSION!!
What industrial-grade diamond typically form as single very included crystals? - ANSWER- Bort
What made it difficult for independent claim holders to survive during the diamond rush in South Africa? - ANSWER- Expenses
What metal dominated melts related to CLIPPIR diamond formation? - ANSWER- Iron
What layer is solid but has a portion that is mobile? - ANSWER- mantle
Which of these is a metamorphic rock? - ANSWER- Eclogite
Where do most lithospheric diamonds form? - ANSWER- Mantle keels 1 / 3
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What deposit type produces a higher percentage of gem-quality stones? - ANSWER- Secondary, rock erodes/washes away leaving diamonds
What type of survey helps narrow the search for secondary diamond deposits? - ANSWER- Mineral sampling
How are diamonds recovered? - ANSWER- Sizing, concentrating, and recovery
What is the name of the supercontinent that existed 230 million years ago? - ANSWER- Pangaea
What shadow like line are created by glide planes? - ANSWER- Graining
What is the study of the interaction between matter and light? - ANSWER- Spectroscopy
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What visible surface characteristic of a diamond reflects its internal development? - ANSWER- Growth marks
Why do cutters check for strain before making final cutting decisions? - ANSWER- To avoid damage during the manufacturing process
How are the nitrogen atoms arranged in type IaA diamonds? - ANSWER- Nitrogen atoms are in pairs within the crystal lattice
What is the energy difference between the conduction and valance bands? - ANSWER- Band gap
What might the trade call diamonds colored by N3 and N2 defects? - ANSWER- Cape
What happens to energy as wavelength decreases? - ANSWER- Increases
What is a defect that causes color? - ANSWER- Defects in its crystal lattice
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