# Ozt vs Dwt

Okay…here’s my latest confustion. Can someone please explain ozt
and dwt? I sure would appreciate it. Thank you, again!

Joy
Joy Kiefner
Rhapsody Jewelry Design

Joy,

A pennyweight (dwt) is simply a division of an ounce-- a "troy"
ounce which is an ounce used to measure precious metals. There are 20
dwts in each troy oz.

While ounces differ-- troy, standard (or Avoirdupois) --grams are
always grams.

There are 28.3 (approx.) grams in an Avoirdupois oz. while a Troy
ounce contains 31.1 grams and so is heavier.

A Troy ounce is usually divided into either 20 dwts or 31.1 grams.
One dwt equals 1.55 grams.

What people choose to measure in, either grams or pennyweights, is
really a matter of choice. I most often measure in pennyweights and
covert to grams if I need to. I like being able to divide by 20. My
scales can toggle between grams and pennyweights.

Take care, Andy

A troy ounce is more than 9.7 percent heavier than a standard or
avoirdupois ounce: There are 31.103 g per troy ounce, versus 28.349
g in a standard ounce. A troy pound weighs less than a standard
pound, however, because there are only 12 ounces in a troy pound,
compared to 16 ounces in a standard or international pound. A troy
ounce is used when weighing precious metals such as gold, platinum
and silver; and some other products. For all other weight
measurements, the standard ounce is used. A dwt (pennyweight) is
commonly used for weighing karat gold, and is equal to 24 grains, or
1/20th of a troy ounce, approx 1.5 grams. There are 20 dwt in an
ounce of gold.

``````Okay..here's my latest confustion. Can someone please explain ozt
and dwt? I sure would appreciate it.
``````

one troy ounce = 20 dwt = 480 grains ( 1 dwt = 24 grains )

The confusion arises because troy ounce is used in weighting gold,
while in common use ounce avoirdupois is employed. The later is only
28.3 grams ( 1/16 of pound avoirdupois ) when troy ounce is 31.1
grams. Beginners should watch out for enterprising refiner, who
sells metal using avoirdupois ounce, because prices always in troy
ounces. Using grams is one way to avoid confusion. That said, troy
ounce is extremely useful for jewelers. Notice that there is one to
one correspondence between gold fineness measured in karat ( pure
gold is 24 karat ), and 1 dwt been 24 grains. If one need to alloy
one ounce of 18k, just weigh 18 grains * 20 of pure gold, and 6
grains * 20 of alloy. No need for calculators. Any purity can be
figured out on the back of a napkin.

Leonid Surpin
www.studioarete.com

Excellent Andy. Here’s another usefull measurement.

5 carats = 1 gram

Why would you need this? Suppose you’re buying scrap gold and you
don’t have time to pull the cheap synthetics which the customer
doesn’t want back anyway, or you’re estimating the weight on a custom
job and you want to know how much the clients metal weighs for trade
in or remelting, again, no time to pull thier stone.

David L. Huffman

20 dwt (pennyweights) per troy ounce, 31.1 grams per troy ounce.

David L. Huffman

Hi Joy,

``````Okay..here's my latest confustion. Can someone please explain ozt
and dwt? I sure would appreciate it.
``````

A dwt (penny weight) is 1/20 of a ozt.

Dave