Silver is a precious metal that has been used and valued by humans for thousands of years. In modern times, silver is still prized for its beauty, conductivity, and antibacterial properties. Silver is measured in various units, including pounds and ounces, when it is traded or used for manufacturing purposes. So how many ounces of silver does it take to make one pound? Let’s take a closer look.
Quick Answer
It takes 16 ounces of silver to make one pound of silver. This is because one pound is equal to 16 ounces in the imperial and US customary systems of measurement. For example, if you had 16 one-ounce silver coins or bars, their combined weight would be 1 pound.
The Origin of the Pound Unit
The pound unit originated in ancient Rome as the libra pondo, meaning “a pound weight.” The libra pondo was equivalent to 327.45 grams. When the Roman Empire collapsed, various Germanic tribes used their own units derived from the Roman pound. In England during the Middle Ages, several varying pound units were used. Eventually, the avoirdupois pound was established as the standard.
The avoirdupois pound was divided into 16 ounces, with each ounce equaling 437.5 grains. The grain was the fundamental unit of mass in the imperial system. Over time, the precise mass of the avoirdupois pound was set at 0.45359237 kilograms. This is the International Pound Agreement of 1959.
So in summary, the subdivision of the pound into 16 ounces has its origins in Medieval England, several centuries before the United States existed as a nation. The system was well-established by the time the American colonies adopted the British imperial system.
The Origins of the Ounce Unit
The ounce unit also has its origins in Roman times, derived from the Latin word uncia. The uncia was equal to 1/12 of the original Roman pound (libra). So just as the number 16 carried over to the avoirdupois system, the subdivision of a pound into 12 ounces also endured from ancient times.
The exact mass of an ounce was variable under Roman and Anglo-Saxon systems. But by the time of King Henry VIII in the 1500s, a standard avoirdupois ounce of 437.5 grains was established. Like the pound, the ounce became an entrenched part of the British imperial system of units.
So again, the subdivision of a pound into 16 ounces originated many centuries ago in England. Both the pound and ounce were firmly fixed parts of the weight system inherited by the American colonies from Great Britain.
Defining a Pound and Ounce in the Modern Era
The imperial pound and ounce are still in use today in the United States, Liberia, and Myanmar. However, the United Kingdom and other former members of the British Empire have switched to the metric system.
In the modern international metric system, the base unit of mass is the kilogram. The kilogram is defined by the mass of a platinum-iridium alloy cylinder kept by the International Bureau of Weights and Measures. One kilogram is equal to approximately 2.2 pounds.
The pound is defined in metric terms as exactly 0.45359237 kilograms. An ounce is defined as exactly 28.349523125 grams. So the relationship of 16 ounces to a pound is maintained, even though the metric system has replaced imperial/customary units in science, commerce, and industry worldwide.
Converting Between Pounds and Ounces
Because one pound is defined as 16 ounces, converting between pounds and ounces is straightforward:
- 1 pound = 16 ounces
- 1 ounce = 1/16 pound
Some examples:
- 2 pounds = 2 * 16 = 32 ounces
- 5 ounces = 5 * (1/16) = 0.3125 pounds
- 24 ounces = 24 * (1/16) = 1.5 pounds
To summarize:
- To convert pounds to ounces, multiply the number of pounds by 16
- To convert ounces to pounds, divide the number of ounces by 16
Converting Other Units to Pounds and Ounces
We can also convert between pounds/ounces and other units of measurement:
Grams to Ounces Conversion
- 1 ounce = 28.3495 grams
- To convert grams to ounces: divide grams by 28.3495
Examples:
- 25 grams = 25 / 28.3495 = 0.8818… ounces
- 100 grams = 100 / 28.3495 = 3.5273… ounces
Kilograms to Pounds Conversion
- 1 pound = 0.453592 kg
- To convert kg to pounds: divide kilograms by 0.453592
Examples:
- 1 kg = 1 / 0.453592 = 2.20462… pounds
- 5 kg = 5 / 0.453592 = 11.02311… pounds
Troy Ounces to Avoirdupois Ounces
Precious metals like gold and silver are often measured in troy ounces instead of avoirdupois ounces:
- 1 troy ounce = 1.09714 avoirdupois ounces
- To convert troy ounces to avoirdupois: multiply troy ounces by 1.09714
Examples:
- 10 troy oz = 10 * 1.09714 = 10.9714 avoirdupois ounces
- 100 troy oz = 100 * 1.09714 = 109.714 avoirdupois ounces
So in summary, you can use simple conversions to go between pounds, ounces, grams, kilograms, and troy ounces. The important thing to remember is that 16 avoirdupois ounces always equals 1 avoirdupois pound.
Measuring Silver in Ounces and Pounds
Now that we’ve looked at the general relationship between ounces and pounds, let’s specifically examine measuring silver.
Like other precious metals, silver is measured by troy weight in many contexts. The troy system is a specialized system just for precious metals, not the everyday imperial/avoirdupois system.
The main units of troy weight are:
- Grain: 1 troy grain = 0.0648 grams
- Pennyweight (DWT): 1 troy DWT = 24 troy grains = 1.55517 grams
- Troy Ounce (ozt): 1 troy oz = 480 grains = 31.1035 grams
- Pound (lb): 1 troy lb = 12 troy oz = 373.242 grams
Although pounds and ounces exist in the troy system, they are not equivalent to imperial/avoirdupois pounds and ounces.
Troy Ounces and Pounds of Silver
When dealing with precious metals like silver, these troy weight conversions apply:
- 1 troy ounce = 31.1035 grams
- 1 troy pound = 12 troy ounces = 373.242 grams
So if you had 12 troy ounces of silver, it would weigh 31.1035 * 12 = 373.242 grams, equal to one troy pound.
Converting Troy to Avoirdupois for Silver
To relate troy pounds and ounces to the more familiar imperial/avoirdupois system, we need to use the conversions mentioned earlier:
- 1 troy ounce = 1.09714 avoirdupois ounces
- 1 avoirdupois ounce = 0.911 troy ounces
Examples:
- 1 troy pound (12 troy oz) = 12 * 1.09714 = 13.1657 avoirdupois ounces
- 13.1657 avoirdupois ounces = 13.1657 / 16 = 0.82285 avoirdupois pounds
So a troy pound of silver is equivalent to 13.165 avoirdupois ounces, or 0.8229 avoirdupois pounds.
Price of Silver per Ounce
When buying and selling silver, the price is usually quoted in US dollars per troy ounce. For example, if silver costs $20 per troy ounce, then:
- 10 troy ounces would cost 10 * $20 = $200
- 1 troy pound (12 troy ounces) would cost 12 * $20 = $240
Apps and websites that display silver prices, like Kitco, always list the per troy ounce price. To calculate the total price of silver in pounds or kilograms, you need to convert the quantity to troy ounces first.
The price of silver fluctuates daily based on market forces of supply and demand. But assuming a hypothetical $20 per troy ounce rate, you can calculate the cost of any silver purchase.
Calculating Silver Content and Value
Precious metals like silver are not 100% pure – they contain other metals blended in. The purity of silver is stated in percentage terms, such as “99.9% pure silver.”
Coins and bullion are produced at various purity levels. The most common is .999 pure or 99.9% silver content.
To calculate the actual silver content of a coin or bar, you need to know both its purity percentage and total weight.
Example Silver Coin Calculation
Let’s say you have a 1 troy ounce silver coin that is 99.9% pure silver.
Total coin weight: 1 troy oz
Purity: 99.9% = 0.999 pure silver
Silver content: 1 troy oz x 0.999 = 0.999 troy oz pure silver
If silver costs $20 per troy ounce, then:
Value = Silver content x Price
Value = 0.999 x $20 = $19.98
So the 1 ounce coin with 99.9% purity contains 0.999 troy ounces of pure silver valued at $19.98 at a market price of $20 per ounce.
Calculating Silver Content in Sterling Silver
Sterling silver is 92.5% pure silver, with 7.5% copper and other metals.
To calculate pure silver content:
- Total item weight x 0.925 = Pure silver weight
- Pure silver weight x Current silver price = Total value
Example:
- Sterling silver bar weighs 5 troy ounces
- Silver content = 5 x 0.925 = 4.625 troy oz
- At $20 per troy ounce, value = 4.625 x $20 = $92.50
You can use this method to calculate the silver value of any sterling silver item once you know its weight and purity.
Measuring Quantities of Silver
When measuring substantial volumes of silver, bullion dealers typically use kilograms or tonnes rather than pounds and ounces:
- 1 tonne = 1,000 kilograms = 32,150.746 troy ounces
- 1 kilogram = 32.150746 troy ounces
Large quantities of silver are expressed in tonnes, kilograms, or millions of ounces rather than pounds. Some examples:
- A standard silver bar traded on futures exchanges like COMEX is 1,000 troy ounces.
- Large bullion banks store silver in 1,000 ounce bars totaling several million ounces.
- The annual worldwide silver production is around 25,000 tonnes.
However, retail bullion products like coins and rounds are still described in troy ounces or pounds.
So in summary:
- Retail silver is measured in troy ounces or pounds
- Bulk silver traded by banks and exchanges is measured in tonnes/kilograms
Conclusion
To conclude, it takes 16 regular avoirdupois ounces to equal one avoirdupois pound. But when dealing with precious metals like silver, the troy system is used instead. One troy ounce is 1.097 ounces in the avoirdupois system.
The key facts to remember are:
- 1 troy pound = 12 troy ounces = 373.242 grams
- 1 troy ounce = 31.1035 grams
- The price of silver is quoted in dollars per troy ounce
So now you know the relationship between pounds and ounces, you can easily convert between the two units. Understanding troy vs. avoirdupois ounces is also important when calculating the quantity and value of silver.
