Silver and gold both fell Friday but the white metal was off proportionately more because unlike gold, which is a pure play store of value, silver has a significant and growing role in various industrial applications.

When economic activity declines or threatens to decline, it affects the price of silver on the futures markets in a way that does not apply to gold.

The thing that's driving the euro down is concern over the Greek debt situation and, in turn, that is sort of a negative influence on economic growth in Europe, said William Adams of FastMarkets.com. Because silver has industrial uses as well as being a precious metal silver can be dragged down when the economic outlook deteriorates.

Silver on the Comex was down about 1.75 percent in midday trading, while gold was off approximately 0.086 percent.

The proportionately greater decline in the price of silver in relation to gold was reflected in the prices of companies that mine silver versus gold and exchange-traded funds that focus on silver or gold.

SPDR Gold Trust was off 0.7 percent while shares of iShares Silver Trust was down 0.36 percent.

Large silver miners were off as much as 5 percent. Coeur d'Alene Mines Corp. fell 2.56 percent, First Majestic Silver Corp. declined 3.08 percent and Silver Wheaton Corp. retreated 2.14 percent.