Question 1

How many points in a carat?

Accepted Answer

1 carat = 100 points. A 0.75 carat diamond is 75 points. Points allow precise diamond weight without decimals.

Question 2

Why use points instead of fractions of carats?

Accepted Answer

Points are clearer: "50 points" is precise. "Half carat" could mean 0.45-0.55 ct. Jewelers prefer points.

Question 3

Is there a difference between mass and weight?

Accepted Answer

Yes! Mass (kg) is amount of matter, constant everywhere. Weight (newtons or pounds-force) is gravitational force on mass, varies by location.

Question 4

Why do jewelry and precious metals use different units?

Accepted Answer

Troy system (troy ounces, pennyweights) has been used for precious metals since the Middle Ages. 1 troy oz = 31.1g vs 1 regular oz = 28.35g.

ct to pt Converter

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