金 (jīn) means "metal" or "gold" and is one of the Five Elements (五行) in Chinese philosophy. In everyday language, 金 often refers to gold or money, as in 金色 (golden color) or 金钱 (money). As an element, it represents strength, rigidity, and autumn.
她戴着一条金项链,非常漂亮。
tā dài zhe yī tiáo jīn xiàngliàn, fēicháng piàoliang.
She's wearing a gold necklace — it's very beautiful.
金是五行之一,代表秋天。
jīn shì wǔxíng zhī yī, dàibiǎo qiūtiān.
Metal is one of the Five Elements, representing autumn.
这枚戒指是纯金的,价格不便宜。
zhè méi jièzhǐ shì chún jīn de, jiàgé bù piányi.
This ring is pure gold; it's not cheap.