Guides

Plain-English answers with the numbers worked out, grouped by the question that brought you here: what it is worth, whether it is real, what to buy, how it should fit, and how to keep it.

Selling gold

What a piece is worth melted and what a buyer will pay

Gold filled valueGrams and dollars by stamp, and who buys it

375 stampNine karat gold, its value and US rules

750 stamp18 karat, its value and the marks beside it

10k vs 14k vs 18kPrice per gram, hardness and which to buy

Real or fake

Stamps, hallmarks and tests that prove something

Real or fakeTests that prove something and tests that do not

Gold testersElectronic, acid, XRF: what each one sees

Hallmarks by countryUK, France, Italy, India, Russia, US: who guarantees what

Buying

Layers, karats, colors and the stores that sell them

Filled vs platedLayer thickness, wear and what each is worth

Plating thicknessFlash, standard and micron plating in months

Plated vs steelWhich cheap gold look actually lasts

Gold colorsAlloys, durability and price of each color

MejuriSolid gold vs vermeil, priced by metal

Ring retailersBlue Nile vs Brilliant Earth in 2026

Kay vs Zales vs JaredOne owner, three storefronts, the real differences

Fit and size

Rings, chains, bracelets and gauges that fit the first time

Chain typesStrength, kinking and repair, style by style

Strongest chainWhich link survives daily wear and a pendant

Wearing and care

Water, tarnish, cleaning, storage and skin

Water and goldShower, pool and ocean by karat and plating

TarnishWhat darkens 14k, how fast, and the fix

CleaningSoap, cloth and ultrasonic: what is safe

StorageTangles, tarnish and scratches, prevented

Green skinWhy it happens and which gold does not do it

Nickel-freeWhich karats and alloys suit sensitive skin

Vermeil lifespanYears by item, and what wears it out

Need a number rather than a page? All calculators, grouped the same way.