Catalysts speed up chemical reactions by lowering activation energy. They don't get used up in reactions, just encourage others to react. Natural catalysts in the body (enzymes) play crucial roles in digestion
Professional cleaning recommended once a year. Jewelry can become treasured heirlooms with proper care. Dust, pollution and daily wear can cloud gemstone brilliance
Precious metals are rare, naturally occurring elements with high economic value. They are corrosion-resistant, ductile, and lustrous. Gold, silver, platinum, and palladium have ISO 4217 currency codes. Historically command higher prices than common industrial metals
Noble metals are generally resistant to corrosion and found in nature in raw form. Term dates back to late 14th century. Odling published first noble metals table in 1864
Aqua regia is a mixture of nitric and hydrochloric acids in 1:3 ratio. Freshly prepared aqua regia is colorless, turning yellow, orange or red. It dissolves noble metals like gold and platinum
Auctions occur twice daily at 09:45 and 14:00 London time. No auctions take place on UK Bank Holidays. Christmas and New Year's Day are treated as half days during December