Gold prices are rallying, but retail gold dealers and shops are struggling to survive.

Yet sales this year of American Eagles, a popular gold coin and a proxy for retail sales of physical gold, have fallen to their lowest levels since 2007, according to the U.S. Mint.

The weak demand is taking a toll on gold dealers, some of whose sales have dropped as much as 70% compared with last year, according to Jeffrey Christian, managing partner at market-research firm CPM Group.