What is worth more a big diamond or a bucket of gold coins?

Your answer, of course, depends on the quality of the items you're comparing. 'Big' is relative for a diamond; 'bucket' is also relative in terms of capacity.

By weight, generally, a gem-quality diamond will be more valuable than an equal weight of gold coin. However, the comparison may be problematic. For example, a one-ounce US gold eagle coin contains 31.1 grams of 24 carat gold. This translates to 155.5 carats in diamond weight.

One notable diamond, The Liberator, was purchased by Harry Winston as a 155.5 carat, raw -- uncut -- diamond in 1943, and was cut into four gem stones. The prices of the four gems -- all D colour -- with values unavailable are in private collections.

On April 6, 2015, the spot price of gold per gram is US$1,212. A cut diamond weighing 21.7 carats -- the largest diamond available for purchase today online -- costs US$1,760,304 or US$405,600 per gram. This is an H colour diamond.

In this comparison, then, a gem-quality diamond outweighs a gold coin in terms of 'worth'.