I originally reviewed What Color Is Your Parachute? in five parts, which you can find here, here, here, here, and here if you would like to read the original comments. What Color Is Your Parachute? is the eighteenth of fifty-two books in The Simple Dollarâs series 52 Personal Finance Books in 52 Weeks.
Thallium is extremely soft, malleable and sectile enough to be cut with a knife at room temperature. It has a metallic luster that, when exposed to air, quickly tarnishes to a bluish-gray tinge, resembling lead. It may be preserved by immersion in oil. A heavy layer of oxide builds up on thallium if left in air.
In the presence of water, the poisonous thallium hydroxide (TlOH) is formed. Thallium dissolves slowly in hydrochloric acid and dilute sulfuric acid and dissolves rapidly in nitric acid. Thallium sulfate, which is odorless and colorless, was used as a rat poison and as an insecticide. This use has been discontinued in some countries, including the USA. Thallium sulfide is used in photocells because its electrical conductivity increases on exposure to infrared light. Thallium oxide is used to make glass that has a high index of refraction.