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Experts Corner



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This area is for general questions about antiques, precious metals, jewelry, and related topics. Have you ever wondered what the four Cs of a diamond are or what the karat system for gold means? What about how the prices of precious metals are set? If you have, you’ve come to the right place. Take a look below for answers from the experts. If your question is not addressed below or on the FAQ page, please feel free to submit your question through the contact page.


An antique is any item in which its age increases its value. In most cases, the age of the item has made the item scarce and thus more expensive and harder to obtain for the collector and the seller.


In a strict sense, vintage is used for wines and should include a date. Its common usage in the antique business, refers to anything that is old enough to have come back into style. While its not technically considered an antique, if an item is back in "style" it would be considered vintage. Vintage can be highly subjective, however, if you would like clarification on any particular item, please feel free to contact me.


Signatures, stamps, and other markings certainly make it easier to determine who created the piece of art but they are not the only indication. When trying to find out the maker of a piece there are several other methods other than actual markings. Experts will look at the style of the piece and try to determine the year that it was made. That helps narrow down the possible makers. In addition to that, experts will also consult other dealers and official catalogue books to determine if the work is a known one. With enough time, effort, and expertise, the maker can usually be determined.


An estate sale occurs when someone wants to sell a large quantity of items usually due to a move, divorce, or death. Unlike a garage or yard sale in which the owner sells the items piece meal, in an estate sale, the owner offers the entire estate. In some cases the buyer will arrange for the sale to be held on the premises of the estate. The buyer will pay a fee to do this and all money generated will be his. In other cases the buyer removes all the items from the estate and sell them outside the premises.


The four C's of diamond quality set forth by the Gemological Institute of America (GIA) are color, clarity, cut, and carat.

Color - For diamonds, the evaluation of color is actually based on the lack of color, with the absence of color being the best grade. The GIA's scale goes from D (colorless) to Z (light yellow). In many cases the color differences between adjacent grading letters is invisible to the untrained eye.

Clarity - Diamonds being a natural substance often times contain imperfections. In the diamond business, the internal imperfections are called inclusions and the outside imperfections are referred to as blemishes. The GIA clarity has six categories for these imperfections. Going from best to worst, they are Flawless (FL), Internally Flawless (IFL), Very Very Slightly Included (VVS), Very Slightly Included (VS), Slightly Included (SI), and Included (I).

Cut - While intuitively you think cut would describe the shape of the diamond, it is actually a grade of how well the diamond's faces interact with incoming light. This is the hardest value to determine. The grading scale consists of five grades: Excellent, Very Good, Good, Fair, and Poor.

Carat - This is a measure of the diamonds weight. One carat is equal to 200 milligrams. Each carat can be broken down into 100 units referred to as points.


The Gemological Institute of America (GIA) is a non-profit institute and the worlds authority on diamonds and other gem stones. When a gem stone has been GIA graded it means that the stone had been analysed by the GIA on the basis of the 4Cs; color, clarity, cut, and carat. These gems will come with a signed document that includes a plotted diagram of clarity characteristics.


Naturally, diamonds come in many colors, black being just one of them. The black diamonds you see for sale today were either created naturally or artificially. Naturally occurring black diamonds are created by inclusions of a black substance like graphite or hematite when they were being formed deep in the earth's crust. These naturally occurring diamonds are quite rare and expensive. Black diamonds created synthetically usually start with a low grade diamond that has been heat treated, irradiated, or treated with a black coating. These lower quality diamonds do not command the same prices as the naturally occuring ones. As with any diamond, ask to see a GIA certified grading with the four Cs.


Blood diamond or conflict diamonds are those diamonds mined in a combat zone. These diamonds are often being mined and sold to support the war effort of whom ever is in power in that particular location. An international effort is under way to ensure that diamond mined and being sold in the open market are not contributing to war efforts in the mined country.


Precious metals such as gold, Silver, and Platinum are traded daily on the global market. They are a global commodity with thousands of uses out side of their use as jewelry. As such, their prices fluctuate hourly. In the United States the main exchange for precious metals is an entity formally known as the Commodity Exchange (COMEX) before merging with the New York Mercantile exchange.


Karats is a measure of fineness of a base substance (in our case gold) to other alloys mixed with it. The system for gold has a maximum amount of 24 karats. 24 karats is equivalent to 100% gold. The equation is karats/24 to find the amount of gold versus the other alloys. For example, a 14 karat ring consists of 14/24 = .5833 or 58.33% gold and 41.67% other alloys. Gold in a pure state is a very soft (malleable) metal. To strengthen gold addition alloys, like copper or even platinum, are mixed in.


gold filled- This is a process where a thick layer of gold is fused with a core of non-gold material.

gold plated - gold plating is a process whereby an almost microscopic layer of gold is electroplated on top of another alloy, not mixed in. In some cases this is done to make more affordable jewelry while still giving it the gold look. In other cases it is done to allow an object to posses the strength of the underlying material but appear to be made of gold.


Silver -Items marked silver or pure silver in the United States contain 99.9% silver.

Sterling Silver- Sterling Silver in the United States is any items that is made with 92.5% silver and 7.5% alloys, most commonly copper. The added alloys give this metal added strength so that it can be used in things like serving wear. These additional alloys, however, cause silver to tarnish

Note* These values are for silver made in the United States. Silver from other parts of the world may be marked Silver or sterling but contain lower ratios of silver to added alloys. Be careful and always check the stamp.


Scrap jewelry is any item that has more value being broken into its constituent parts and sold separately (a process commonly referred to as scrapping) rather than being sold as a single piece of jewelry. There are many reason why this can be the case. The two most common reasons is that the piece is so "out of style" that selling it as a whole is problematic. The second reason is that the piece is either damaged of broken and not worth fixing. So, check your jewelry box. That old or broken piece of jewelry you haven't worn in years can still be very valuable.


Costume jewelry is any jewelry that is made of metals other than Gold, Sterling Silver, or Platinum. It is also used to describe jewelry that is made of gold under 10 karats.


The U.S. Mint and many others use the American Numismatic Associations (ANA) grading system. This system is a graduated grading system with the the following grades:

Perfect Uncirculated (MS-70) - Perfect condition, showing no indication of wear
Choice Uncirculated (MS-65) - An above average uncirculated coin
Uncirculated (MS-60) - No trace of wear but shows contact marks
Choice About Uncirculated (AU-55) - Very little evidence of light wear on the highest areas. Most of the mint luster remains
About Uncirculated (AU-50) - Has little evidence of light wear on the highest areas. Half of the mint luster remains
Choice Extremely Fine (EF-45) - Has evidence of light wear on the highest areas. Some of the mint luster remains
Extremely Fine (EF-40) - Lightly worn throughout. Traces of the mint luster may remain
Choice Very Fine (VF-30) - Lightly worn throughout
Very Fine (VF-20) - A moderate level of wear throughout
Fine (F-12) - Shows moderate to considerable level of wear throughout
Very Good (VG-8) - Well worn with major features still clear
Good (G-4) - Heavily work with design visible but faint
About Good (AG-3) - Very heavily worn. Lettering may be unreadable


Un-Circulated -Every coin starts out as un-circulated. When a coin is struck at the mint it is considered in un-circulated condition and will remain that way until either it goes into circulation or is damaged. These coins have a grade between MS60 and MS70.

Proof - Proof coins are never intended to be in circulation. They are only struck for the collector market. Normally a coin is struck once under normal pressure but a proof coin is struck twice creating a mirror like background. These also are graded between MS60 - MS70.

Circulated - A circulated coin is any coin, even a proof, that has made its way into the general circulation of money.

For more information see the U.S. Mint information page


Bone China - Bone China is made of cow bone ground into an ash that is added to feldspar, clay, and quartz. Bone China should contain at least 30% bone but can contain as much as 40 - 45%. This mixture is moulded and then fired at around 2,200 0 Fahrenheit. Bone China has a more warm color than China and if held to the light, has a more translucent quality.

China - Is made the same way minus the bone ash. Compared to Bone China, regular China has a brighter white color.

Porcelain - Is made mainly from clay and feldspar. The main difference between Porcelain and China is the temperature at which it is fired. For Porcelain it is fired at around 2,650 0 Fahrenheit. This higher temperature while being fired gives it its added strength.