Shalimar perfume- what is the real price?

How come when I want to buy Shalimar by GUERLAIN the price ranges from $50 to $130? Is the $50 one not genuine?|||The $130 is a parfum and the $50 can be either a cologe, eau de toilette or a perfume. Parfum is always a very small bottle. The price just ranges for what strength you want. You best to go with the $50 because parfum's are a dab on form. Bottles like that ruin faster.