Wahala Facts: 16 most expensive materials on earth

4. Tritium symbol T or 3H, also known as hydrogen-3) is a radioactive
isotope of hydrogen.The emitted electrons from the
radioactive decay of small amounts
of tritium cause phosphors to glow so as to make self-powered
lighting devices called betalights, which are now used in firearm
night sights, watches , exit signs, map lights, and a variety of other
devices. Commercial demand for tritium is 400 grams per year[3] and
the cost is approximately US $30,000 per gram.