Which elements are common in asteroids?
Platinum is rare and expensive on Earth. Dearer than gold or tungsten.
But see
http://en.wikipedia.org/wiki/Cosmochemical_Periodic_Table_of_the_Elements_in_the...
Platinum (1,4 parts per million Si) is the most common element between
lead (3,3 ppm) and barium (4,4 ppm). Far more abundant than gold (0,20
ppm), quicksilver (0,41ppm) or tungsten (0,13 ppm).
Osmium (0,67 ppm) and iridium (0,64 ppm) are also more common than
gold, quicksilver and tungsten.
The heaviest metals that are more common than barium are zirconium
(11,3 ppm), yttrium (4,6 ppm) and strontium (23,6 ppm).
But if you consider trying to mine the sky... what would you go after?
