• お金かね — money
• 金曜日きんようび — Friday
• 金色きんいろ — golden color
• 料金りょうきん — fee / charge
• 貯金ちょきん — savings
• 募金ぼきん — donation

The character “金” is formed from a symbol representing a mine and particles of metal. It’s used widely — from currency and banking to weekdays and elements in chemistry. In its kunyomi form かね or かな, it appears in common nouns. The rarer こがね means “gold” in a more poetic sense.