From the point of view of durability capital is distinguished as fixed and circulating. From the point of view of mobility or readiness to be changed from one use to another, it is distinguished as free and specialized. If, for example, capital goods can be readily changed from one use to another we designate them free capital. On the other hand, if capital goods must be used for a particular purpose and cannot be diverted to another use without serious loss, we say that the capital goods are specialized. As an example of free capital goods we may cite coal, which can be used in many different kinds of production, and if it becomes necessary to stop one kind of production for which the coal has been purchased, it can readily be used in some other kind of production without loss. On the other hand, capital invested in a creamery building cannot readily be turned to another use if the production of butter at that place be discontinued. Such capital is specialized capital.