The Royal Canadian Mint unveiled a welcome addition to any piggy bank on Thursday — a monster gold coin with a face value of C$1 million (U.S. $903,000) that it says is the world's biggest, purest and highest denomination coin.

Weighing in at 100 kilograms (220.5 pounds), the limited edition coin easily dwarfs its closest rival, the 31-kg (68-pound) "Big Phil", which was made to honour the Vienna Philharmonic Orchestra and has a face value of a mere 100,000 euros (U.S. $136,000).

The Canadian mint introduced the mega-coin, which is the size of an extra-large pizza, alongside the one-ounce gold bullion coins it is mass producing at its Ottawa plant.

Originally designed to promote the new one-ounce coins, the colossal 100-kg coins will be produced in a very limited quantity.

A U.S. precious metals distributor has ordered three and there is interest in Asia and Europe, the mint said.

At 53 centimetres (21 inches) in diameter and over 3 cm (1.2 inches) thick, the massive coins need a high level of hand crafting.

While it has a C$1 million face value, the coin is worth more than twice that amount — about $U.S. 2.4 million — given the current gold price of $U.S. 686.90 an ounce.

The new coins are both adorned with a maple leaf and boast 99.999 percent purity, a notch above previous purity peaks of 99.99 percent.

"Since the Royal Canadian Mint upped the ante on the rest of the world in 1982, by raising the purity of gold bullion to four nines pure (99.99 percent) other nations have come on the scene ... Austria, the United States, and Australia being the case in point," said mint spokesman Alex Reeves.

"We compete for market share with all of these countries and we decided that the time was right to do something to stand out from the crowd once again."

Bullion and refinery services generated almost C$281 million in revenue in 2006, more than half the mint's total sales of almost C$494 million.