Hike distance; 7.1 miles
California’s largest state park, Anza-Borrego, protects 600,000 acres of desert terrain, including dramatic badlands, cool palm oases, twisting slot canyons, and cactus-studded slopes. This desert preserve pairs the name of famed Spanish explorer Juan Bautista de Anza, who crossed the desert in 1774, and the Spanish word for sheep (“borrego”)—referring to the region’s native bighorn sheep. The park’s striking landscape is in continual flux from flash floods, seismic action, and erosion. This map shows the location of this gem of a state park in relation to more commonly known locations in southern CA.
The calcite mine trail is accessible right off S22 around mile marker 34. We started the hike by descending from S22 into the Palm Canyon Wash and then we began a gradual climb along the far side of the wash before heading NW up the hill (marked in yellow).
The trail continued on a plateau that offered great views of the surrounding hills.
The trail followed a road that had been used during the WWII when calcite was mined here; now there are only a few traces of the road remaining.
Patches of desert lilies lined the trail.
So beautiful despite very little water being available to support them.
Just below the ridge were the sediment walls of the Palm Wash.
Some of these hills resembled the landscape in Death Valley with the mineral colored hillsides.
Narrow canyons display the incredible power of flowing water which eroded deep gashes through the sandstone.
We finally reached a spot with views of the Salton Sea.
Numerous examples of wind and rain erosion in the rock face.
After about 2 miles of hiking we reached a sign that marked the mine entrance.
Calcite is a common mineral, a form of calcium carbonate, similar in basic chemical composition to chalk and gypsum and is a basic material for cement. There are at least 800 different forms of crystalline calcite. These differ in color and in light transmission from completely opaque to translucent. The calcite crystals mined here were colorless and transparent.
Calcite was an essential component of the Norden bombsight. The Norden bombsight was one of America’s most closely guarded secrets during World War II. It was the state of the art in the 1940s and used to calculate the trajectory of a bomb being dropped from high altitudes. It enabled American airplanes to hit ground targets in daylight raids from an altitude of six miles.
Calcite was mined by digging trenches along calcite-containing seams. The trenches can be recognized by their unnatural regularity. Small calcite crystals were everywhere glistening in the sun light.
You could see mine trenches slashing through the terrain.
Our lunch-time location was a hilltop a short walk away.
We had perfect lunch-time views.
On our way back, we explored one of the many side canyons.
The canyon narrowed the further we traveled.
and just like that, we reached a 20+ foot dry fall that prevented us from going further.
We weren't ready to give up so we headed back to the main canyon and followed a different wash.
This trail was more enjoyable since it quickly turned into a slot canyon, but
it came to an abrupt ending with another dry fall that was impossible to maneuver around or down.
We returned to the main canyon and instead of following the mine road we headed into the Palm Canyon wash.
The wash narrowed and they became smooth as glass.
Water from recent rains or percolating groundwater made for some slow going.
The wash widened again and we were back to walking through soft sand and boulder fields.
Unfortunately, we missed the spot where the wash turned back to the trail head. It was a nice day to extend the hike but we needed to find a location where the canyon walls gave way to hills that we could scale to get back on the trail.
After scrambling up a few hills, we found the trail back to our starting point ...only a few extra miles.
the planned trail our actual path
A few extra miles, but well worth it.