Many metals are not found in nature in their elemental form, but in minerals which are a combination of elements. The metal is extracted by various means from these minerals. Sphene is a mineral containing titanium (Ti) and has the empirical formula CaTiSiO5. Calculate the proportion by mass of titanium in Sphene. Give your answer as a percentage to 2 significant figures. You will need to consult the Periodic Table in Book 4, page 48, to obtain the relative atomic masses of the elements in the mineral.