Market Vectors Gold Miners (NYSEArca: GDX) and Market Vectors Junior Gold Miners (NYSEArca: GDXJ) have been decimated by the two-day sell-off in gold.

GDX was down 8% in morning trade Monday to its lowest level since January 2009.

Its small-cap sibling, GDXJ, dropped 10% to a fresh all-time low.

Gold futures were down sharply after Friday’s plunge, losing $100 an ounce to drop under $1,400 for the first time since March 2011.

However, miner ETFs continue to fall harder than bullion prices. GDX is down 42% for the trailing six months, compared with a loss of 20% for SPDR Gold Shares (NYSEArca: GLD). [Gold Sell-Off Hammers Miner ETFs]

“Gold miners were having a tough ride before gold started tumbling, as investors demanded less growth and more costs cutting from the industry. The precious metal’s freefall is now adding to their pain,” reports Ben Levisohn at Barron’s.

Market Vectors Gold Miners

Full disclosure: Tom Lydon’s clients own GLD.