14K AND 10K GOLD
All gold has a karat number that indicates its gold content. The karat system tells you how much gold a piece has based on 24 parts.
So 24k gold is pure gold because it contains 24 of 24 parts. The higher the karat number, the more gold a piece has.
The lowest karat number you can sell in the United States is 10k gold since it is only 10 of 24 parts, or 42% gold. The other 58% is made of alloyed metals.
The most common alloyed metals include copper, zinc, nickel, and silver. Natural gold is always yellow gold, but jewelers can create different colors by changing the type of alloyed metals. An alloy with a high copper percentage creates rose gold. Bright white alloys, like zinc and nickel, make white gold. White gold can also be covered in a layer of bright white rhodium for an even more brilliant hue.
14K Gold Advantages and Disadvantages
Advantages: A great mix of purity, durability and value for money.
Disadvantages: More expensive than 10K gold, but still fairly affordable.
14 karat gold is made up of 14 out of 24 parts gold. 14K gold is the most popular gold for rings and other wearable jewelry in the United States. 14K gold has a rich color, with the classic gold appearance that most customers look for in rings and other jewelry. Its color is slightly less saturated and intense than 18 karat gold, making it an excellent choice if you want gold jewelry that’s rich and attractive but not overly yellow.
About 90% of all engagement and wedding rings are made from 14K gold.
10K Gold Advantages and Disadvantages
Advantages: Very affordable, more durable than other types of gold.
Disadvantages: Pale yellow color, more likely to trigger metal allergies.
10 karat gold is made up of 10 out of 24 parts gold. 10K gold is the least pure, least expensive and most durable form of gold used in jewelry. Although it’s widely used in earrings and affordable jewelry, 10K gold isn’t a very popular metal for engagement rings and fine jewelry. Aesthetically, 10K gold has a pale appearance, with a significantly less rich yellow tone than 14K. The biggest advantages of 10K gold are its cost and durability. Since it has the lowest gold content of any type of gold, 10K gold is also highly durable. It’s very difficult to scratch, scuff or bend jewelry made from 10K gold. The main disadvantage of 10K gold is if you’re allergic to copper, silver, nickel, zinc, or iron, it’s possible for your skin to irritate if you wear a 10K gold ring for a long period of time.
Gold-filled jewelry is composed of a solid layer of gold (typically constituting at least 5% of the item's total weight) bonded to a base of either sterling silver or a base metal.
Gold-filled pieces have the same appearance as high carat gold, and even with daily wear, can last years though the layer of gold will eventually wear off exposing the metal underneath.
Vermeil consists of a base of sterling silver coated or plated on all significant surfaces with gold of not less than 10-karat, that is of substantial thickness and a minimum thickness throughout equivalent to 2 1/2 microns of fine gold.
Gold plating is a method of depositing a thin layer of gold onto the surface of another metal, most often copper, brass or silver, by chemical or electrochemical plating.
The thickness of gold plating on jewelry is noted in microns. The microns of thickness determines how long the gold plating lasts with usage. The jewelry industry denotes different qualities of gold plating in the following terminology
Gold plated - gold layer thickness greater than or equal to 0.5 micron
Heavy gold plated / Vermeil - gold layer thickness greater than or equal to 2.5 micron.
Gold plated jewelry can still tarnish as the base metals diffuse into the gold layer, causing slow gradual fading of its color and eventually causing tarnishing of the surface. This process may take months and even years, depending on the thickness of the gold layer.
Sterling silver is an alloy of silver containing 92.5% by weight of silver and 7.5% by weight of other metals, usually copper. The sterling silver standard has a minimum millesimal fineness of 925.
Fine Silver, for example 99.9% pure silver, is relatively soft, so silver is usually alloyed with copper to increase its hardness and strength. Sterling silver is prone to tarnishing.
Millesimal fineness is a system of denoting the purity of platinum, gold and silver alloys by parts per thousand of pure metal by mass in the alloy. For example, an alloy containing 75% gold is denoted as "750".
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