This periodic table shows the locations of Iridium (Ir, atomic number 77), Sulphur (S, atomic number 16), Carbon (C, atomic number 6), Oxygen (O, atomic number 8) and the Rare Earth Elements, (R.E.E.). The Rare Earth Elements are the group of elements from Lanthanum (La, atomic number 57), to Lutecium ( Lu, atomic number 71).