RAWALPINDI, Pakistan — The price of gold has shot up by 450 percent in the past decade. So it might seem like street sweepers, collecting gold dust discarded by jewelers, are in the right place at the right time to make a decent profit.

But the increase in gold prices means consumers are buying less jewelry, and craftsmen are making fewer new pieces. Fewer scraps are falling on the streets, and an already dangerous job has become even harder.