CBJ Skills and Expertise 3 — Questions and Answers
Question 1: When channel-setting square princess-cut stones, what is the most critical measurement to verify before setting?
- The total carat weight of all stones combined
- The stone width versus channel width tolerance (Correct answer)
- The girdle thickness of each stone
- The table percentage of the center stone
Correct answer: The stone width versus channel width tolerance
The stone width must match the channel width within a tight tolerance so stones sit level and the channel walls can be burnished over the girdles evenly.
Question 2: Which finishing technique is used to create a matte, non-reflective surface texture on metal?
- Rouge polishing
- Sand blasting or brushing with a brass wheel (Correct answer)
- Burnishing with a smooth steel tool
- Applying a bright-cut engraving
Correct answer: Sand blasting or brushing with a brass wheel
Sand blasting or wire/brass brushing creates a uniform fine texture that scatters light, producing a matte surface finish.
Question 3: In platinum fabrication, why must tools and work surfaces be kept free of gold contamination?
- Gold raises platinum's melting point significantly
- Gold can diffuse into platinum at high temperatures, causing yellow discoloration (Correct answer)
- Gold residue prevents platinum from being polished
- Gold contamination makes platinum brittle at room temperature
Correct answer: Gold can diffuse into platinum at high temperatures, causing yellow discoloration
Gold can diffuse into platinum at soldering temperatures, causing permanent yellow discoloration that cannot be polished out.
Question 4: A bezel-set cabochon stone sits too low after setting. What should the jeweler have done differently during fabrication?
- Used harder metal for the bezel
- Made the bezel seat shallower so the stone sits higher (Correct answer)
- Applied more flux before soldering the bezel
- Chosen a lower dome height for the cabochon
Correct answer: Made the bezel seat shallower so the stone sits higher
A shallower seat (the ledge inside the bezel) raises the stone's sitting height so more of the cab is visible above the bezel wall.
Question 5: What is the purpose of a scribe in bench jewelry work?
- Measuring ring sizes accurately
- Scratching layout lines on metal for cutting or forming guides (Correct answer)
- Cleaning flux residue from solder joints
- Pressing prongs over a stone's girdle
Correct answer: Scratching layout lines on metal for cutting or forming guides
A scribe scratches fine lines onto metal to mark cut lines, centerlines, or reference points before sawing or forming.
Question 6: Which solder flow property is described as the temperature at which solder becomes fully liquid and flows freely?
- Solidus temperature
- Liquidus temperature (Correct answer)
- Annealing temperature
- Recrystallization temperature
Correct answer: Liquidus temperature
The liquidus temperature is the point at which solder is completely molten and flows into the joint by capillary action.
Question 7: When performing a two-piece ring shank sizing job, what must a jeweler verify before soldering the new shank section?
- The ring's appraisal value matches records
- Alignment is true so the ring is not twisted after joining (Correct answer)
- The gemstone's fluorescence grade
- The original solder grade used in prior repairs
Correct answer: Alignment is true so the ring is not twisted after joining
Proper alignment before soldering ensures the shank is not twisted and the ring sits level on the finger after the repair.
CBJ Skills and Expertise 3
When channel-setting square princess-cut stones, what is the most critical measurement to verify before setting?