Last year, on a hike up Vanier Mountain nearby Kusawa Lake, my friend spotted a black and white mountain across the lake. The north side of the pyramid-shaped mountain was black and the south side white.

It was mysterious to me. How could one side be black, and one side be white? I dug a little deeper.

Geologically, Kusawa Lake is in the middle of the Coast Plutonic Complex, which runs from Alaska into British Columbia. Through time magma cooled underneath the earth’s surface, and here at the Coast Plutonic Complex, that cooled magma is now the rocks we climb on. And in this area, the rocks we climb on are typically is made up from granite and diorite.

I see now that the black and white mountain we were climbing is indeed granite. The black side is solid granite, and it’s black because of a crust of lichen. The white part, which, when I got close-up turned out to be beige, is disaggregated granite (I got that word from my neighbour, a geologist). He calls it friable or gruss granite. I brought him some of the coarse beige sand from the black and white mountain, which he confirmed was probably fallen apart coarse-grained granite.

It is an amazing site. This whole mountainside is a sandy slope; a few plants hang on for dear life, no lichen grows here, the mountain eroding before our eyes. It gives the impression of a vertical desert.

When my friend spotted the mountain a year ago, I was instantly interested, because I had made some futile attempts to climb the mountain in front of it.

Later at home, looking at satellite images, I saw that the mountain I had approached also had a white south slope. I resolved to climb that front mountain to the summit and follow the ridge to the south end. Many attempts later I have finally succeeded, thanks to Darren Holcombe and his wife Lara Melnik, my companions on this attempt.

We were early at our meeting point on the Kusawa Road and began hiking at 10 o’clock, starting at the far campground and following the beach due south.

We gained elevation quickly and I was exhausted as we reached the ridge at 1 o’clock. Glorious ridge-walking is easier than the steep climbing; it’s undulating, but still gaining height.

The top is around 4,700 feet (1,432 metres). We saw the black and white pyramid mountain to the west, coming out at the white side of this ridge, and we stood in awe. As we played in the sand, we decided this was far enough for today. Although we were tempted by the call of further summits, they will still be there for another day.

We went back through a crack in the mountain, due north towards the creek. We spotted a pika in the canyon, and the canyon soon brought us to alpine meadows. Heading back into the trees we got a little lost, but, miraculously, Darren lead us straight to the van: we came out of the thick forest right where we parked… now how’s that for serendipity?

Though we were back by 6 p.m., it was a very tough hike.