The definition of antique varies from source to source, product to product and year to year. These are some time test definitions of antique for you to consider.

An item which is at least 100 years old and is collected or desirable due to rarity, condition, utility, or some other unique feature. ...

 

antique (noun) -
	1. any piece of furniture or decorative object or the like produced in a former period and valuable because of its beauty or rarity