Although small-scale prospecting is resurgent as commodity prices rise, with families even booking vacations to pan for gold or wield a pick, that type of activity just won't cut it these days. Global demand for metals, coal, and anything else that must be dug out of the Earth is so immense that it demands massive and highly specialized machines. That's where Bucyrus (NYSE: BUCY) comes in, designing and building the modern-day equivalents of yesterday's picks and axes.

Alongside competitors Joy Global (NYSE: JOYG) and Terex (NYSE: TEX), and related plays like Caterpillar (NYSE: CAT) and Deere (NYSE: DE), Bucyrus has seen its shares rise steadily as the global commodities boom garners further investor interest. Today's earnings results seem to more than justify that confidence.

Compared with first-quarter 2007, Bucyrus reported a greater-than-170% increase in sales, to $516 million. Operating earnings rose 140% to $67 million, and diluted net earnings rose 91% to $1.09 per share. Just as impressively, the company kept gross profit margins steady at 27.4% year over year, even as rising costs plagued many other manufacturers.

With mining activity this robust, simply building the machines is not enough. As anyone with a vehicle can attest, there is plenty of money to be made in parts, and these particular machines aren't likely to get the same tender treatment Fools bestow on their own rides. Though Bucyrus is presently completing plant expansions that will yield an additional 24 mammoth shoveling machines per year, the company's doubling of its capacity to produce manufactured parts (from 2006 levels) may be even more significant.

In another significant development, which mirrors recent results from rival Joy Global, Bucyrus's backlog is ballooning. With strength deriving from both the surface mining and underground segments, and originating from markets across the globe, the company reported a 40% increase in backlog orders, from $1.4 billion to more than $2 billion. Roughly 75% of the total backlog will translate to sales over the coming 12 months, with the other 25% providing a head start for subsequent years.

A broad swath of equipment manufacturers seem particularly strong right now, provided their equipment relates to commodity extraction. Fools shouldn't be scared away by these lofty heights, though; the underlying phenomenon is real, and no signs of reversal seem to lurk on the horizon.

A rich vein of further Foolishness:

Fool contributor Christopher Barker captains yachts and writes about stocks. He can also be found acting Foolishly within the CAPS community under the username Sinchiruna. He owns no shares in the companies mentioned. The Motley Fool has a disclosure policy.