Under the rules of medieval heraldry, gold and silver were classed together as “metallic” colors, but could not be used on top of one another in a coat of arms. That relationship between the two is similar in the world of finance today, where gold and silver are both classified as “precious metals,” but are really two different metals with two different tendencies.

This week’s exchange-traded fund (ETF) spotlight on the iShares Silver Trust (SLV) will be a deviation from the various gold funds I’ve been featuring but it still will be within my current theme of examining promising precious metals ETFs.

SLV was founded in 2006 and it is not your standard ETF. The trust is not an investment company registered under the Investment Company Act of 1940 nor is it a commodity pool under the Commodity Exchange Act. Shares of the trust are subject to the same requirements as a mutual fund. SLV’s purpose is, generally speaking, to reflect the price of silver owned by the trust at that time and give investors exposure to the day-to-day movement of the price of silver bullion.