The key U.S. equity gauges were in the red on Thursday. Among the top ETFs, investors saw (SPY Quick QuoteSPY - Free Report) lose about 0.6%, (DIA Quick QuoteDIA - Free Report) shed over 0.5% and (QQQ Quick QuoteQQQ - Free Report) move lower about 0.5% on the day.

Two more specialized ETFs are worth noting in particular though as both saw trading volume that was far outside of normal. In fact, in the most recent trading session, both these funds experienced volume levels that were more than double their average. This could make these ETFs the ones to watch out for in the days ahead to see if this trend of extra interest continues:

(IAU Quick QuoteIAU - Free Report) : Volume 3.49 times average

This retail gold bullion was in focus yesterday as roughly 28.2 billion shares moved hands compared with an average of roughly 8.09 million shares. IAU lost about 1.2% on the day.

Gold prices came under pressure due to the rising greenback. The currency gained strength on increasing odds of a Fed rate hike in the March meeting. In the last one-month period, IAU was up about 1.3%. The fund has a Zacks ETF Rank #3 (Hold).

(DEM Quick QuoteDEM - Free Report) : Volume 3.44 times average

This emerging market ETF was in focus yesterday as almost 1.08 million shares moved hands compared with an average of roughly 314, 340 shares. We also saw some stock price movement as DEM was down about 1.73%.

The decline can again be attributed to rising U.S. Treasury yields. Fears of a cease in cheap dollar inflows on the possibility of faster Fed rate hikes also weighed on this emerging market ETF. In the last one-month period, DEM was up just 0.5%. The fund carries a Zacks ETF Rank #3.

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