The following commentary comes from an independent investor or market observer as part of TheStreet's guest contributor program, which is separate from the company's news coverage.By Paul Tracy NEW YORK ( StreetAuthority) -- He might be one of the most unheralded investors of modern times. The Globe and Mail newspaper called him "Canada's 'Hidden Billionaire.'" Others have referred to him as the "Warren Buffett of Canada." No matter what you call him, Eric Sprott is undoubtedly one of the world's most successful investors. Earlier this year, Sprott Inc., his investment company, announced its assets under management had exceeded $10 billion. Bloomberg estimates Eric Sprott himself has a net worth of at least $1.3 billion. So what is this billionaire investing mogul buying now? Silver... and lots of it. His flagship mutual fund, the Sprott Canadian Equity Fund, holds 25% of its assets, worth about $400 million, in silver bullion. Another 15% is held in silver equities such as stock of mining companies. Why is he so bullish? In an October interview, Sprott provided plenty of reasons. According to U.S. Mint statistics, the same amount of money that is going into buying silver bullion is going into buying gold bullion. With gold trading at more than 50 times the price of silver, this means investors are buying 50 times the amount of silver from the U.S. mint as gold. China used to export 100 million ounces of silver just a few years ago. Now they import 100 million ounces each year. In the physical market for silver, Sprott says, "All I'm seeing are buyers." The price ratio between gold and silver used to be 15 or 16:1. Now it's more than 50:1. Meanwhile, silver in the Earth's crust is just about 15 times more abundant compared to gold. According to numerous sources, Sprott says gold and silver should be trading at a 16:1 ratio. This means with gold at $1,600, silver should be changing hands at about $100 an ounce -- 245% higher than the current level of $29 per ounce. The interesting thing is that it seems like the "Warren Buffett of Canada" isn't alone in having a bullish stance on silver. Demand for American Silver Eagles has been skyrocketing for years, indicating regular investors are highly bullish on silver as well.