Is gold magnetic?
No. Real gold is not magnetic. Pure gold is diamagnetic, which means a magnet very slightly repels it, an effect far too weak to feel by hand. If a "gold" chain, coin or ring snaps onto a magnet, it contains a magnetic metal such as steel or nickel under the plating, and it is not solid gold.
The catch: a magnet test catches steel fakes but not all fakes. Copper, brass, lead and tungsten are also non-magnetic, so a piece that ignores the magnet has only passed one cheap screen, not proven itself. That is why we XRF test free at the counter: the machine reads the exact metal composition in seconds, in front of you, with no damage to the piece.
How much does a brick of gold weigh?
The movie-style gold brick is a real thing: the Good Delivery bar held in central bank vaults. Its standard weight is about 400 troy ounces, roughly 27 pounds, packed into a bar about the size of a small loaf of bread. That surprising density is the point; gold is one of the heaviest common metals, which is why a fake bar of the right size almost never has the right weight.
| Gold bar | Weight | Metal value right now |
|---|---|---|
| Good Delivery brick (vault standard) | About 400 troy oz, roughly 27 lb | — |
| Kilo bar | 32.15 troy oz (1 kg) | — |
| 10 oz bar | 10 troy oz | — |
| 1 oz bar | 1 troy oz | — |
Note the unit: bar weight is quoted in troy ounces, which are heavier than kitchen ounces. Our troy ounce guide covers the conversion, and the gold biscuit price page prices the smaller minted bars people actually own and sell.
Are gold nuggets worth more than melted gold?
Often, yes. Natural gold nuggets carry collector premiums above melt value: a well-formed nugget with character can sell for more than the same weight of refined gold, because collectors pay for the shape, the rarity and the story. Crushing a nice nugget into scrap pricing is leaving money on the counter.
Searching "gold nuggets near me" with something to sell? We buy natural nuggets at all 8 of our NJ counters, weigh and XRF them in front of you, and check the collector angle before quoting melt. The gram math for any gold, nugget or not, lives on the scrap gold value per gram page.
What is gold used for?
Jewelry takes roughly half of the world's annual gold demand, and investment bars, coins and central bank reserves take most of the rest. The remainder does real work: gold's perfect conductivity and refusal to corrode put a trace of it in nearly every phone, computer and satellite, and it also appears in dentistry, medical devices and spacecraft coatings.
That demand mix is why the price moves the way it does, part fashion, part fear, part industry. The gold price history page shows how those forces have played out over the decades.
How is gold tested?
Three methods dominate. The acid test touches a scratch of the metal with karat-graded acids and watches the reaction; it is cheap but it scratches the piece and only reads the surface. The specific gravity test weighs the item in air and in water to check its density against gold's; it needs no chemicals but struggles with stones and hollow pieces. XRF, the modern professional standard, reads the exact composition in seconds with no damage at all.
We use XRF at every counter, free, with the reading on the screen in front of you. Watching your own karat number appear is the single best protection a seller has, and it is the standard our sell gold page walks through step by step.
Can gold rust or tarnish?
Pure gold cannot rust or tarnish. Rust is iron oxide, and gold contains no iron; more broadly, gold simply refuses to react with oxygen, water or most chemicals, which is why coins recovered from centuries-old shipwrecks come up gleaming.
Gold alloys are another story. The copper, silver and nickel mixed into 10k, 14k and 18k jewelry can discolor, darken or leave skin marks over time. A tarnished piece has lost none of its gold content, only its shine, and it sells for exactly the same melt value as a polished one. Check the current number any time on the live gold price page.
What is the density of gold, and what are the gold symbols and stamps?
Gold density is 19.3 grams per cubic centimeter, nearly twice lead. That heft is why fakes fail the scale and why a small bar feels so improbable in the hand.
Gold symbols: Au on the periodic table
Gold's chemical symbol is Au, from the Latin aurum. On jewelry, the symbols that matter are the karat stamps: 10k, 14k, 18k, 22k and 24k, or their European equivalents.
Gold stamp number codes: what 999, 750, 585 and 417 mean
The three-digit number codes are purity in parts per thousand: 999 is pure gold, 750 is 18k, 585 is 14k (58.5 percent gold), and 417 is 10k. A stamp is a claim, not proof, which is why we XRF every piece anyway.
What is placer gold?
Placer gold is natural gold eroded out of rock and concentrated in stream gravel: the flakes and nuggets panners recover. We buy placer gold by weight and XRF reading, and check nuggets for collector value first.
The gold rush, defined: fun facts about it
A gold rush is a mass migration to a new gold discovery. The California rush of 1849 drew some 300,000 people, San Francisco grew from a village to a city in two years, and most fortunes were made selling shovels, not finding nuggets. The gold those miners chased is chemically identical to the gold in your jewelry box.
How is white gold made, and does gold turn green or tarnish?
White gold is real gold alloyed with white metals such as palladium, silver or nickel, then usually plated in rhodium for brightness. That is what white gold is made of: the karat stamp still tells you the gold content underneath.
White gold cost per gram: is white gold more expensive than yellow gold?
At the counter, no. White gold cost per gram follows the same karat math as yellow: 14k white and 14k yellow contain identical gold and melt for the same figure. Retail prices differ because of rhodium plating and fashion, not metal content.
Different shades of gold color
Alloying explains every shade: copper makes rose gold, silver and palladium make white, more copper and silver together tune yellow from pale to rich. Green-tinged gold, called electrum, is a gold and silver mix. All of them sell on karat and weight.
Does gold turn green, and will it turn your skin green?
Solid gold will not turn green. When skin turns green under a ring, the copper in a low-karat alloy or a worn-through plating is reacting with sweat. The gold content is unaffected and so is the melt value.
Does 18k gold tarnish, and will 18k gold plated jewelry tarnish?
Solid 18k gold is 75 percent pure and barely tarnishes; at most it dulls slightly as the alloy metals react. Gold plated pieces are different: once the thin layer wears, the base metal underneath will tarnish freely. Plated items carry almost no melt value, and an XRF reading tells the difference in seconds.
How many carats is pure gold, and what is the highest karat?
Pure gold is 24 carats: that is the highest karat of gold there is. Anything stamped higher is not a purity mark. Jewelry runs 10k to 22k because pure gold is too soft for daily wear.
Can you test gold with a lighter?
The lighter trick, heating a piece to see if it darkens, is a crude screen at best: real gold will not oxidize black, but plenty of fakes survive the flame too, and you can scorch a good piece. Skip it. The XRF reading at our counter is free and touches nothing.
What is antimony? The metal's chemical symbol, element facts and symbolism
Antimony is a brittle, silvery metalloid, element 51, and its chemical symbol is Sb, from its Latin name stibium. It is not a precious metal and carries no melt value at a counter like ours, but it earns its place in metal trivia twice over: antimony hardens the lead alloys in old pewter and type metal, and its symbolism runs deep in alchemy, where its symbol stood for the wild, untamed side of nature. If a mystery bar or figurine turns out to be antimony or pewter rather than silver, the free XRF reading says so in seconds, before anyone's hopes get ahead of the metal.
Physical precious metals: how a purchase and a sale work in the metal marketplace
Physical precious metals means the real thing you can hold, bars, coins and jewelry, as opposed to paper claims on metal. The metal marketplace for physical pieces runs on the live spot price plus or minus a premium: a purchase from a dealer costs a little over spot, and a sale to a buyer like us pays relative to the same live number, with collectible pieces earning above it. We are on the buying side every day at all 8 counters, and the live prices this site displays are the same feed the offer is built from.
Curious what your own gold really is? Bring it in: XRF tested free in front of you, priced from the live market, paid the same day. Call (732) 483-4145.
Find your nearest of our 8 storesGold facts FAQs
Will real gold stick to a magnet?
No. Real gold is not magnetic, so a piece that snaps onto a magnet contains steel or nickel and is not solid gold. But copper, brass and tungsten also ignore magnets, so passing the magnet test proves nothing by itself. An XRF reading, which we run free, settles it.
What is the weight of a standard gold brick?
The Good Delivery bar, the brick in every vault scene, weighs about 400 troy ounces, roughly 27 pounds. The table above prices that weight against the live gold feed, and it is a number that surprises everyone who lifts one.
Where can I sell gold nuggets in New Jersey?
At any of our 8 counters: Aberdeen, Brick, East Brunswick, Farmingdale, Manalapan, Middlesex, Millstone and New Brunswick. Natural nuggets are weighed and XRF tested in front of you, and we check for a collector premium above melt before quoting.
Can I test gold at home?
You can screen it: a magnet catches steel fakes, and a careful density check catches some others. But home tests cannot read karat or catch every counterfeit, which is why the professional standard is XRF. We run it free at the counter with no obligation to sell.
Does tarnished gold jewelry lose value?
No. Pure gold cannot tarnish, and when an alloy discolors it is the copper, silver or nickel reacting, not the gold. The full gold content is still in the piece, so a dark, dull chain sells for the same melt value as a polished one.