The ruby is the most valuable red gem except for the red diamond.  It come in many shades of red.  Natural rubies can be very expensive but lab grown rubies have the same properties and cost considerably less.
Ruby is said to bring joy, understanding and material gain.  It is said to bring it's owner romance, prosperity and generosity.  As a red stone, ruby energizes the lower chakra or energy center in the groin area, so would be beneficial to those who have health problems in that part of the body and those who have auras weak in red.