CBJ Metal Properties and Alloys

Question 1

What karat value represents pure gold?

Accepted Answer

24K

Answer

Pure gold is 24 karat, representing 100% gold content with no alloying metals.

Question 2

Which precious metal used in jewelry has the highest melting point?

Accepted Answer

Platinum

Answer

Platinum melts at approximately 1,768°C, the highest melting point among common jewelry metals.

Question 3

What percentage of silver does sterling silver contain?

Accepted Answer

92.5%

Answer

Sterling silver is 92.5% pure silver alloyed with 7.5% other metals, typically copper, indicated by the .925 hallmark.

Question 4

What property describes a metal's ability to be drawn into wire without breaking?

Accepted Answer

Ductility

Answer

Ductility is the property that allows metal to be stretched or drawn into wire without fracturing.

Question 5

Which alloying metal primarily gives yellow gold its hardness and warm color?

Accepted Answer

Copper

Answer

Copper is the primary hardening alloy in yellow gold and contributes to its warm yellow-orange tone.

(CBJ) Certified Bench Jeweler Practice Test