Sodium: geological information

Sodium is never found as the free element ("native") in nature as it is so reactive. Sodium is the sixth most abundant element in the earth's crust at about 2.6 - 3.0%. The most common mineral is rock salt (sodium chloride, NaCl, or halite), but it occurs in many other minerals including sodium borate (borax), sodium carbonate (soda), sodium nitrate (Chile saltpetre). and sodium sulphate (thenardite). In those species, however, it is the anions that are the reason for mining.

Sodium is present in some abundance in the sun and other stars andclearly identifiable by the sodium D lines which are very prominent in the solar spectrum and those of other stars.

Abundances of sodium in various environments

In this table of abundances, values are given in units of ppb (parts per billion; 1 billion = 109), both in terms of weight and in terms of numbers of atoms. Values for abundances are difficult to determine with certainty, so all values should be treated with some caution, especially so for the less common elements. Local concentrations of any element can vary from those given here an orders of magnitude or so and values in various literature sources for less common elements do seem to vary considerably.

Abundances for sodium in a number of different environments. Use the links in the location column for definitions, literature sources, and visual representations in many different styles (one of which is shown below)
Location ppb by weight ppb by atoms
Universe 20000 1000
Sun 40000 2000
Meteorite (carbonaceous) 5600000 4800000
Crustal rocks 23000000 21000000
Sea water 11050000 2970000
Stream 8000 350
Human 1400000 380000

The chart above shows the log of the abundance (on a parts per billion scale) of the elements by atom number in our sun. Notice the "sawtooth" effect where elements with even atomic numbers tend to be more strongly represented than those with odd atomic numbers. This shows up best using the "Bar chart" option on the chart.

cartogram depicting abundance of elements in the earth's crust
A cartogram depicting the abundance of elements in the earth's crust. Squares for each element are distorted in proportion to the numerical value of the abundance.

WebElements chemistry shop

You can buy periodic table posters, mugs, T-shirts, periodic table fridge magnets, games, molecular models, and more at the WebElements periodic table shop