Why is an alloy considered a mixture even though it cannot be separated by physical methods?

An alloy is considered a mixture even though it cannot be separated by physical methods as it shows the properties of its constituents and can have variable composition. The proportions of the constituent elements in an alloy can be varied within certain limits. An alloy exhibits the characteristic properties of the metals from which it is made. While typical mixtures can often be separated by simple physical methods like filtration or evaporation, alloys require more complex processes.