This is a National Park so there is no collecting. The coordinates take you out a little way past the paved interpretive trail. The logging questions do reference a couple of the interpretive panels. You can follow one of established trails out to the coordinates. Following the infrequent rains, you may find the trail muddy and slippery.
Boron forms over 100 different minerals. This group of minerals are called borates. Because of boron’s strong attraction to oxygen, all of these minerals contain boron and oxygen.
Borates are either anhydrous (the crystal structure does not contain water) or hydrous (the crystal structure does contain water). Anhydrous borates are rare and are typically found in igneous and metamorphic rocks. Hydrous borates are much more common and typically form as evaporates on desert playas.
Three borates are commonly found in Death Valley. They are
Name |
Formula |
Borax |
Na2B4O7 10H2O |
Colemanite |
Ca2B6O11 5H2O |
Ulexite |
NaCaB5O9 8H2O |
These minerals are typically soft and white, but can be colorless or transparent. Beyond these three there are at least 22 other borates found in the park, but they are much less common. The one pictured here is colemanite
Borate deposits in Death Valley are found in either Holocene lake playas on the valley floor, or in the Pleistocene (6-4 million year old) Furnace Creek Formation. In both cases, the borates precipitated in shallow lakes. The borates in the Furnace Creek Formation are thought to have entered ancient lakes through hot springs or altered rhyolite from the nearby volcanic fields. These Pleistocene lakes existed before the formation of the current Death Valley
Logging requirements:
Send me a note with :
- The text "GC5X6V9 Death Valley Borates" on the first line
- The number of people in your group (put in the log as well).
- How does the borate mineral look at this location?
- Based on the informational signs, which borate mineral was mined here?
- Based on the informational signs, how do the borate minerals get to the valley floor?
- Looking at the location of the crystals, are borates continuing to be deposited?
The following sources were used to generate this cache:
- Cal Poly Geology Club Death Valley Field Trip – 2004 Guidebook by Don Tarman & Dave Jessey http://geology.csupomona.edu/docs/DVT2004.pdf
- http://geomaps.wr.usgs.gov/parks/deva/fthar4.html
- http://www.nps.gov/deva/learn/historyculture/harmony.htm
- http://www.nps.gov/deva/learn/nature/mining-in-death-valley.htm
- http://geomaps.wr.usgs.gov/parks/deva/fthar3.html
- http://cornellbiochem.wikispaces.com/Borax
- http://www.realgems.org/list_of_gemstones/colemanite.html