I looked at the films of all 116 directors who had at least five movies on my list of 2,200 top US-grossing films (1994-2015). The table below shows the 30 directors who make Hollywoodâs longest movies.
A gold alloy that is 50% gold and 50% other metals is 12 karat gold because it is only half pure gold. Alloys used in jewelry making range from 9 karat gold, which is approximately 37% gold, to 24 karat gold, and are required to be stamped and hallmarked according to purity.y mixing gold with other metals, or alloying it, gold is made stronger, which makes it durable enough to wear more often without experiencing wear. A variety of metals are commonly used to alloy gold, including silver, copper, nickel, iron, zinc, tin, manganese, cadmium, and titanium.
White gold and sterling silver pieces often contain a metal called nickel which can cause allergic reactions in some people. Stainless jewelry can be (but is not always) made without nickel making it suitable for those allergic to nickel.latinum jewelry is usually 95% pure platinum with other metals added to improve the shine and luster of the final piece. Platinum jewelry is usually marked with a number between 800 and 1000. This number correlates to the percentage of platinum used in the metal with 800 being 80% and 1000 being 100%.