Rubies are precious gemstones that range in color from light pink to blood red and are second only to the diamond in hardness. They are found chiefly in Myanmar, Thailand, and Sri Lanka and are classified among the most valuable of gems. The rare star ruby, which shows an internal star-shaped formation when cut into a cabochon, is an example of a gemstone whose value is actually increased by an inclusion. Why can rubies be found beneath building foundations in some Asian countries? Discuss