Homage To Granite: Urban Climber Magazine

 This article originally appeared in Urban Climber Issue 36.

Homage: Granite – Great Stone… or the Greatest Stone?

By Sarah Garlick from UC #36 > February 2010

Choosing a favorite stone is like choosing a favorite color: pointless . . . and maybe even a bit childish. Still, while I don’t think I’ve had a favorite color since grade school, ask me what’s my favorite rock, and I won’t hesitate: it’s granite. Granite is El Capitan, in Yosemite; Hampi, India; and the Buttermilk boulders of Bishop. Granite is Joshua Tree; City of Rocks; and Rocky Mountain National Park. From The Mandala to Midnight Lightning to the Nose to Eternal Flame, this one wonderful stone comprises many of the world’s most inspiring climbing areas and climbs. So what makes granite granite?

Granite is a type of intrusive igneous rock, which means it forms from the slow cooling and solidification of magma — liquid rock — deep underground. This slow cooling gives granite that hard, rough texture that chews your fingertips and shoe rubber. The time the magma takes to cool dictates the size of the crystals: a long, slow cooling process allows ample time for large coarse crystals to grow, forming, for example, the sharp, knobby faces in Vedauwoo and Joshua Tree.

To be a true granite, the rock has to have certain minerals: roughly equal amounts of quartz, plagioclase, and potassium feldspar. Those are the grayish-clear, white, and pinkish flecks in the stone. Some rocks end up having more or less of these components, and thus have different names. A rock with less potassium feldspar is called a granodiorite, while a rock with less quartz is called a monzonite. But these are still considered part of the granite family, and they basically climb the same, so for most purposes it’s fine to just call them all granites.

Granite can be carved into high, alpine needles or sheer, blank walls, but one of the most fun and interesting forms granite takes is that of big, round boulders. Like some prehistoric giant’s lopsided eggs, granite boulders from Vedauwoo to Bishop to Joshua Tree all have a similar character: low, steep underbellies (which, with luck, are cut with crimpers and flakes) that roll up into broad, blank, rounded top-outs. I remember the first time I saw the Peabody boulders in Bishop. I was surprised by how exquisitely shaped and sculptural they were . . . and also how intimidating. What would it be like to climb on those upper faces, crimping on tiny crystals and flakes, praying they stay attached? And then there is the Balance Boulder, at Vedauwoo’s Nautilus: a huge, rounded egg perched atop a low crag, supported by what seems to be only few points of contact. Last I heard, the boulder hadn’t yet been freed.

Such rounded granite boulders are called core stones, and they form during the weathering of granite bodies at the Earth’s surface. The reason the Buttermilk, Vedauwoo, and Joshua Tree boulders seem so similar is they’ve all been shaped by essentially the same process. It takes four steps, and a whole lot of time, to make these big granite eggs:

The granite bodies form miles underground, slowly cooling into solid rock from huge chambers of hot magma.

The solidified hunks of granite become uplifted and eventually exposed on the Earth’s surface.

As the granite is uplifted, it cracks, typically in a couple of predictable orientations. Vertical fractures — called joints — form when the granite body is squeezed and stressed by the large-scale movements of the Earth’s tectonic plates. As the granite is further uplifted it becomes depressurized and another set of fractures form, this time roughly horizontal, parallel to the granite’s surface. These two crack systems divide the granite body into blocks and pillars.

As the granite approaches the Earth’s surface, groundwater penetrates the crack systems. Water doesn’t dissolve the granite, but chemically alters some of its minerals, causing the rock to fall apart. This is how crumbly, kitty-litter granite is formed. Eventually, as the granite becomes uplifted and exposed to the air, wind and rain carry away the disintegrated rock, leaving the core stones behind.

But not all granite boulders are core stones. Core stone boulders have essentially weathered in place, but rock fall can also create boulders. In many alpine environments, freeze-thaw cycles cause huge chunks of stone to spall off cliffs and roll down to valley floors. Many of the massive boulder fields in places like Rocky Mountain National Park and Yosemite National Park formed this way. Glaciers can also carry, sometimes for long distances, and drop boulders. These so-called glacial erratics are common across New England and Europe. Boulders that form from rock fall, and even some glacial erratics, are usually less rounded and egg-like than core stones; they’re more angular and feature fewer crumbly sections . . . but they can also be pretty blank.

Everyone seems to have his or her own idea of what it means to climb granite. Some people think of run-out slabs, others trad crack climbs or big aid routes. But to learn the true art of granite climbing is to learn more than just one discipline. This one stone requires a spectrum of skills: pulling out an overhang to a highball slab; delicate smearing; jamming a crack; slapping your way up an overhanging arête. It’s granite’s variability that I love the most — and it’s this variability that forms some of the best playgrounds of the vertical world.

Sarah Garlick is the author of Flakes, Jugs & Splitters: A Rock Climber’s Guide to Geology. She lives in The Granite State with her husband Jim, president of Granite Films, where their local crags are made up of the Conway Granite.