Scrap Jewelry Calculator

Not Reviewed
Calculator / Last modified by pro on 2016/05/26 15:48
Metal and alloy pricing
Buy Price: Gold Alloy
Buy Price: All Alloy
Junk Silver Value
Platinum SPOT $/Oz
Gold SPOT $/Oz
Palladium SPOT $/Oz
Silver SPOT $/Oz
All Metals Bullion Value
Round Faceted Emerald Cut Faceted
Pear or Teardrop Long Rectangular Cut
Cabochon Cut Navette or Boat
Cushion Faceted Square Cut Faceted
Heart Shape Marquise Faceted
Specific Gravity Oval Faceted
Round Brilliant Triangular Brilliant
Oval Brilliant Marquise Brilliant
Heart Shaped Pear-shape Brilliant
Emerald Cut Tapered Baguette
Baguette Old European
Princess Cut Cushion

The Scrap Jewelry Calculator will accurately tell you the current scrap value of the precious metals in your jewelry and provide accurate carat (weight) estimates on your gems.  Gem weights are based on their shapes (e.g. cabochon) and dimensions.  These calculations include special functions for diamonds.  VIDEO INSTRUCTIONS

Current SPOT

Metal$ / gram$ / troy oz
Gold $48.84019$1519.1
Platinum $30.70396 $955.0
Palladium $52.92012 $1646.0

Scrap Metal Value Instructions

Gold Using Karat Rating

if you have scrap gold, the purity is either in karat or percent pure.  If your gold has a karat value, use the Buy Price: Gold Alloy formula:

  1. Enter the weight of you gold. Note: there are several unit choices including grams and troy ounces.
  2. Enter the karat rating
  3. Enter the refiner's fee.  Note: this can range from 8% for gold with few other components (metal, gems) to 50% for complex jewelery.
  4. Enter the fee (profit).  This is the reasonable profit that the scrap gold buyer should get for the transaction.

The Buy Price: Gold Alloy formula will then compute the "Buy Price" with matches the above characteristics, which is the reasonable price that a jeweler or precious metal recyclers will pay to BUY your gold.  This is useful for gold buyers (jewelers etc) and gold sellers.

Any Precious Metal using % Purity

If you have other precious metals (platinum, palladium or silver), or if your gold is rated in % purity, use the Buy Price: All Alloy formula formula:

  1. Choose the precious metal (gold, platinum, palladium or silver),
  2. Enter the purity percentage
  3. Enter the refiner's fee.  Note: this can range from 8% for metals with few other components (metal, gems) to 50% for complex jewelery.
  4. Enter the fee (profit).  This is the reasonable profit that the scrap metal buyer should get for the transaction.
    The formula will return the "Buy Price" with matches the above characteristics.  This is useful for precious metal buyers (jewelers etc) and sellers.

The Buy Price: All Alloy formula will then compute the "Buy Price" with matches the above characteristics, which is the reasonable price that a jeweler or precious metal recycler will pay to BUY your scrap precious metals.  This is useful for precious metal buyers (jewelers etc) and sellers.

Junk Silver Value

Junk Silver is U.S. coins that predate 1964 and therefore have a substantial silver content.  These are coins with no numismatic value (coin collectors value for rarity etc).  These are typically common and/or very worn coins.  To compute their value:

  1. Enter the number of coins you have by denomination (silver dollars, silver half dollars, quarters and dimes)

The Junk Silver Value formula will compute their total value based on an industry formula and the current SPOT price of silver.


The Scrap Jewelry Calculator has three tabs (sections) where one can find equations and data useful for Jewelers and other merchants of gems and precious metals. The three sections with equations are Metal and alloy pricing, Gem carat estimate, and Diamond carat estimate.

Metal and Alloy Pricing

The precious metal equations provide the current (2 minute latency) value (SPOT price) of platinum, gold, palladium and silver.  These spot prices are queried every two minutes from an online service linked to the precious metal commodity markets and given in dollars (U.S.D.) per troy ounce. 

Jeweler's Buy Price Equations

The Jeweler's Calculator provides two equations to assist the Jeweler is establishing the "Buy Price" for scrap metals.  Both equations calculate the price that the jeweler can pay for scrap based on the following:

  • The current spot price of the refined precious metal.
  • The amount of refined precious metal in the scrap
  • The refiners fee that jeweler has to pay
  • The amount of profit that the jeweler wishes to achieve in this transaction.

Buy Price Instructions:

  1. The jeweler ascertains which precious metal is in the scrap (platinum, gold, palladium or silver). 
  2. The jeweler ascertains the purity as either a karat (k) or percentage.  Karat values are converted to percentages inside the Jewelers calculator automatically.
  3. The jeweler weighs the scrap.  The Jeweler calculator accepts the most common weight units including grams and troy ounces.
  4. The jeweler enters the cost of refining as a percent of the transaction (e.g. 5% refinement fee)
  5. The jeweler enters the desired profit as a percent of the transaction (e.g. 12% profit).
  6. The jeweler calculator will then use these factors along with the most recent spot price for the precious metal to calculate the price the jeweler should be willing to pay for the scrap precious metal based on a spot price that is up to date within the last two minutes.

The Buy Price: Gold Alloy equation is only for gold and only allows the purity to be entered as a karat (k).  The Buy Price: All Alloy lets the jeweler select the precious metal (platinum, gold, palladium and silver) and accepts the purity as a percentage.

The precious metals currently include: gold, platinum, palladium and silver


The equations for diamonds and gems provide the approximate carat AllCuts.png Different Gem Cuts weight of a gem based on its shape and dimensions.  These equations approximate the volume of the gem and use the specific gravity to provide a karat weight estimate.  The different weight approximations are based on the shape of the gem (see list of cuts below). The vCalc library containing these equations is under Earth Science / Mineralogy / Gemology.

The gems include: Agate, Alexandrite, Almandite garnet, Amethyst, Aquamarine, Beryl, Bloodstone, Blue topaz, Carnelian, Cats eye, Chalcedony, Chrysoberyl, Citrine, Corundum, Demantoid garnet, Diamond, Emerald, Golden beryl, Green beryl, Kunzite, Lapis lazuli, Morganite, Onyx, Opal, Precious topaz, Pyrope garnet, Quartz, Rose Quartz, Ruby, Sapphire, Sardonyx, Smokey quartz, Spessartite garnet, Tanzanite (zoisite), Topaz, Tourmaline, Tsavorite garnet, Turquoise, Yellow topaz, Zircon.

The gem cuts include: round (circular), oval, emerald cut, long rectangular, square, navette or boat-shaped, pear-shaped or teardrop, cabochon, princess cut, Cushion cut, Old European cut.


The Diamond Weight tab contains carat weight equations that are specific to diamonds and diamond cuts.

NOTE: Never use an estimating equation for the weight of a gem if you can weigh it on a quality jeweler's scale.  These equations are useful when the jeweler is trying to preserve the setting of the gem while still providing a carat weight estimate.  In this way, the jeweler can ascertain the type of gem, its shape and then using precise measuring tools measure the salient dimensions for use in these equations.  These steps can be done while the gem remains in the setting.

The vCalc Jeweler's calculator is free to use like all the other equations and calculators found in vCalc.  Please feel free to comment on this wiki page using the comment button below and help us make a better Jeweler calculator for you.


This calculator provides Jewelers and other merchants of gems and precious metals to compute an estimated current market value for jewelry items.  Likewise private owners and insurance providers can make similar estimates for use in establishing the basis for insurance valuation and coverage.


The equations and data used in vCalc's jewelry library and calculator were reviewed by a certified gemologist.   The equations are based on industry recognized formulas and data.  The table below shows a comparison of computations between vCalc and an industry accepted application (Quantum Leap).

The length, width and depth are in millimeters (mm), and the Quantum Leap and vCalc measurements are in carats (cwt).


The largest variance, an oval faceted alexandrite, which can be seen in the last row above, has been double checked against several source equations which tend to support vCalc's accuracy.