<P> In the CDP, the population was spread out with 37.3% under the age of 18, 9.4% from 18 to 24, 39.7% from 25 to 44, 13.0% from 45 to 64, and 0.5% who were 65 years of age or older . The median age was 27 years . For every 100 females there were 105.4 males . For every 100 females age 18 and over, there were 103.7 males . </P> <P> The median income for a household in the CDP was $43,500, and the median income for a family was $47,750 . Males had a median income of $40,402 versus $21,250 for females . The per capita income for the CDP was $16,186 . About 1.5% of families and 2.6% of the population were below the poverty line, including 3.8% of those under age 18 and none of those age 65 or over . </P> <P> The desert is located in the Tularosa Basin of New Mexico . Its white sands are not composed of quartz, like most desert sands, but of gypsum and calcium sulfate . Unlike other desert sands, it is cool to the touch, due to the high rate of evaporation of surface moisture and the fact that the sands reflect, rather than absorb, the sun's rays . At 1185 meters above sea level, there are approximately 442 square kilometers of dune fields and is known to be the world's largest surface deposit of gypsum . </P> <P> Gypsum is one of the most common mineral compounds found on Earth but is rarely seen on the surface, as it dissolves easily in water . The origin of this desert dates back to around 100 million years ago, during which it was covered by a shallow sea . As its waters gradually receded, saltwater lakes were left behind, which eventually evaporated in the sun . In addition to the salt, gypsum was also laid down in thick deposits on the old seabed . </P>

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