Question 1

How many grams in a troy ounce?

Accepted Answer

1 troy ounce = 31.1035 grams. This is about 10% heavier than a regular (avoirdupois) ounce at 28.35 grams.

Question 2

Why do precious metals use troy ounces?

Accepted Answer

Troy system predates avoirdupois and has been standard for gold/silver since medieval times. 12 troy oz = 1 troy pound.

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.

Troy oz to Grams Weight Converter - Free Online Tool

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