Titanium, Silver and gold


i wonder why gold and silver are among the most precious metals, even though they are some of the softest (gold). But I really wonder why titanium is even more expensive than these. Gold scratches/dents easier than most metals. Does titanium retain it's characteristics better? What about their respective positions on the periodic table makes them have these properties (gold vs. titanium). Is there a simple atomic reason why titanium holds it's form better than gold?


Any material is worth what people will pay for it. Gold is attractive because it is practically impervious to corrosion and there is not much of it on Earth. I have seen it estimate that the entire quantity of gold on the planet would make up a cube about 45 feet along each edge. Except for small quantities used in research and electronics - gold is an excellent conductor of electricity - there is not much industrial use of gold.

Titanium is the fourth most abundant element on Earth. It is expensive on a per weight basis relative to iron for example because it is difficult to extract from its ore but I doubt it is as expensive per ounce as gold. There are notebook computers being built in a pure titanium box. I doubt if even Apple, a company not known for its good business sense, would pay $286.00 per ounce for their basic structural material. I checked the commodities market for the gold price this morning and found that titanium is not even traded as a precious metal.

Titanium alloys are about as strong as steel and much lighter. In general it is the arrangement of electrons in the outer shell of the atom that determines the hardness and toughness of a metal. Those near the middle of the periodic table tend to be the better structural materials. The details of the crystal lattice structure and strength of the inter-atomic bonds are not simple. They account for variations in strength among materials that are close neighbors in the periodic table.