alexsl/iStock via Getty ImagesThe small-cap equity universe has a reputation as the corner of the market where true gems are hiding, as it is mostly undercovered by Wall Street analysts, so unique growth stories with a potential for outsized returns could go unnoticed and underappreciated. Investors have multiple options to gain exposure to that equity echelon, with the iShares Core S&P Small-Cap ETF (NYSEARCA:IJR), an ultra-low-cost passively managed vehicle, being one of the main examples. IJR might l ...