In nature, sodium is found in the Earth's crust, 2.83 % (w/w) . The isotope found in nature is 23Na (100 %, stable) .
In pure, solid form, sodium exist in a body-centered cubic crystal structure 
Originally Na was produced by reducing Na2CO3 with C :
Na2CO3 + 2 C 2 Na + 3 CO (g)
Currently the process used is electrolysis of melted NaCl .
Cathode: Na+ (l) + e- Na (l)
Anode: Cl- (l) ½ Cl2 (g) + e-
NaCl melts at 801 °C, so the process is carried out in a mixture of NaCl and CaCl2 or Na2CO3 with a melting point of about 600 °C.