Crystal Cave of Giants

Naica, Mexico - Sept. 2009

Air Temperature of 50C(122F) + Relative Humidity of over 90% = Humidex Value of 105C (228F) !!

This is one of the most extreme places on the planet.



Each step had to be placed carefully. One slip and you could fall and become impaled on a crystal.

With such high temperatures, once you step inside the cave, your body begins dying. You are incapable of shedding body heat.

  • The Crystal Cave of Giants was accidentally discovered in 2000 by miners working in the silver and lead mine at Naica, Mexico. It lies almost 300 meters (900 feet) below the surface of the Earth and it contains the largest crystals known in the world, by far. The largest crystals are over 11 meters long (36 feet) and weigh 55 tons.
  • The crystals themselves are made of selenite which is crystallized gypsum, the same material used in drywall construction. Except these crystals formed over a span of about half a million years in a hot water solution, saturated with minerals. The the temperature inside the cave remained very consistently hot for the entire time the crystals were growing.
  • It is still incredibly hot in the cave due its proximity to a magma chamber, deep underground. The air temperature is 50C with a relative humidity of over 90%, making the air feel like an unbearable 105C (228F) Entering the cave without special protective suits can be fatal in 15 minutes. I will be entering the cave wearing a special cooling suit with chilling packs inside and a specialized backpack respirator which will allow me to breath chilled air. Even with all this equipment, I will still only be able to stay in the cave for no more than 45 minutes at a time.
  • In extreme heat, the body begins to lose higher brain functions which made the expedition much more difficult with the risk of falling into deep pits, or being impaled on a sharp crystal. All the camera gear needs to be slowly brought up to temperature beforehand by pre-heating it and most cameras with moving parts and tape mechanisms simply will not work at all.
  • It is as dangerous as it is beautiful.
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    When the call comes over the radio to get out... It is time to go.

    Climbing up onto one of the larger crystals.
  • When we first arrived at the Naica mine, Manuel and his crew took us inside without wearing the special cooling suits. This was in order to get us used to what REAL heat is like. There is a steel door protecting the cave and as soon as you pass through it, the temperature hits you like a truck, but as soon as you get your first glimpse of the incredible crystals, you want to keep going deeper. We were inside for only 14 minutes, which was pushing the danger limits without cooling suits. When we exited, the staging area was a "cool" 41 Celsius. My heart was pounding and I was completely soaked in sweat, my shirts, pants, socks & boots... Everything. All we could do was sit, drink and rest.
  • The next day, the real exploration began. We had left our camera gear inside the cave the night before, sealed up in air tight bags so that it could slowly warm up to the ambient temperature of the cave. Without doing this, all the gear would fog up, form a layer of condensation and become totally useless.
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    Crystallized Gypsum is known as Selenite.

    It looks like a scene from a science fiction movie.



    Nik and I slowly moving across uneven crystal terrain.

    Filming inside the cave... This not simple since the environment inside the cave is so harsh. Our main camera died towards the end of the day.
  • The Suits - The custom designed cooling suits only delay the inevitable. As soon as you enter the cave, you begin to overheat and heat stroke and death are inevitable if you remain inside too long. The suits will extend your stay in the cave but it is up to the individual to recognize when you've been exposed too long. 30-50 minutes is the maximum, depending on the individual.
  • Each suit consists of several layers of protection. First is an insulated vest which protects you from frostbite which you could get from having ice in direct contact with the skin. Then the ice vest which is a series of gel filled pouches, sewn into a mesh vest and kept frozen. This cools you body's core temperature. Overtop of all that is a set of rugged overalls. These keep the radiant heat from the cave away from the ice plus they protect you from the sharp crystals. Last but not least is the respirator pack. This custom built backpack is made of insulating foam and contains frozen metal ice bottles. A fan blows air over the bottles and it is pumped up a hose to a face mask which is similar to the type worn by fighter pilots. This system allows you to breathe chilled air as long as the ice remains frozen in the pack.
  • Wearing the suits, you feel like an astronaut that is about to go on a space walk. In reality, it is not all that different, considering the harsh environment.
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    My adventure partner for this trip, Nik Halik, enjoying the view.

    Inside the "cool" staging area outside the cave. It was 41 Celsius with close to 60% humidity here.
  • Actually going inside, wearing the suits and exploring the cave was a dream come true. I've never seen such a spectacular place. It was like setting foot on a new planet. Many of the crystals were so large that I couldn't even wrap my arms around them and the terrain was so difficult to walk on that we had to be extremely cautious not to slip and fall. Doing so would could get you impaled on a sharp crystal and would require a dangerous and difficult rescue.
  • Each minute you stay inside, the more unbearable it gets. You begin to breathe heavy, your hear rate jumps up and sweat is pouring down your hands. I was actually concerned that the sweat was going to short circuit my camera. It becomes easy to get confused and disoriented from the heat and your higher cognitive functions start to shut down. When you finally leave the cave, your body is so weak that all you want to do is lie down and drink. Dehydration is an obvious concern and I was amazed at how many liters of water I drank.
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    Getting a closer look at the larger crystals.

    Carrying the Explorers Club flag into the cave.



    Manuel keeps track of everyone who enters the cave and how long they've been in.

    Getting my respirator hooked up. This supplied me with cool air to breathe.

  • How it formed - Naica lies on an ancient fault and there is an underground magma chamber below the cave. The magma heated the ground water and it became saturated with minerals, including large quantities of gypsum. The hollow space of the cave was filled with this mineral rich hot water and remained filled for about 500,000 years. During this time, the temperature of the water remained very stable at over 50 degrees C. This allowed microscopic crystals to form and grow. Due to the perfect conditions inside, they were able to keep growing until the silver miners pumped away the ground water in order to explore deeper. They accidentally discovered the cave when they broke through back in 2000. Since the cave is no longer submerged, the crystals have stopped growing and cooler air from the mine is lowering the temperature slightly more each year.
  • When the Naica mine is no longer profitable, it is likely that they will just shut off the water pumps and the crystal cave would then disappear forever.
  • Getting into the cave is a monumental undertaking and requires a huge support crew. We required a medical station with a paramedic, cooling technicians, video monitoring, communications, lighting in the cave, freezers to recharge the cooling suits. The logistics were mind boggling. Many thanks go out to Manuel and his crew from C Productions who were vital in making this entry possible.