How did william seward's purchase of alaska and the aleutian islands become profitable?

The purchase of Alaska was profitable a great deal. First, it must be noted that the purchase was for Geo-political reasons.The actual price was repaid in twenty years through the sale of fur seal skin. In addition, huge deposits of copper,oil and timber hugely exceeded the benefits. currently, it is agreed that the purchase is over 7 times profitable.The fact that the purchase proved profitable implies that the secretary of state was ahead of several of his many critics.