Gold
An element of the Periodic Table. Historically used as a means of exchange.
Until the United States (and the rest of the world) went off the gold standard for currency, the gold price was largely held fixed. In 1964, that price was approximately $35 per ounce. Currently, the price is hovering around $1500.
Speech Relevance
Early in 'A Time For Choosing', Reagan states,
"We have $15 billion in gold in our treasury--we don't own an ounce. Foreign dollar claims are $27.3 billion..."
Reagan is comparing two data points, the value of the United States gold supply used to back up our paper money and the amount of federal debt owned by foreign countries.
Later, he also says,
"In the last six years, 52 nations have bought $7 billion worth of our gold, and all 52 are receiving foreign aid from this country."
Source Links
States Bullion Depository (Wikipedia)
Gold Prices- 1833 to Present (PDF from the National Mining Association)