Solid goldSolid gold is the most expensive and the most high quality option because it is long lasting, doesn’t rub off or flake and doesn’t tarnish. However, it is not 100% solid gold because pure gold is too soft to create durable jewellery. Instead, it is alloyed with a mixture of metals such as silver, copper and zinc. Gold increases in value over time and has the best resale value.24K or 24-karat is 100% pure gold.18K or 18-karat is 75% gold and 25% alloyed metals.14K or 14-karat is 58% gold and 42% alloyed metals.Gold-filledGold-filled jewellery is gold bonded with another metal such as brass or copper. The gold layer is 5% of the total gold weight. Gold-filled is an economical alternative to solid gold. If taken care of, it can last as long as solid gold and will not tarnish or rub off. Reselling it though would not have as much value as solid gold.Gold vermeilGold vermeil is similar to gold plated jewellery except the layer of gold is thicker and the metal underneath is sterling silver. It lasts longer than gold plated jewellery but can still tarnish when exposed to water, sweat, perfume, and the gold may eventually scratch or rub off with wear.Gold-platedGold-plated jewellery has a base of some other metal like brass, covered with a thin layer of gold. This is on the lower end of the price spectrum. Gold-plated jewellery tarnishes and rubs off easily, revealing the metal underneath.