Following is a list of exceptions to the above rule: a sealed barrel of libation wine mixed even with a thousand barrels of kosher wine, an idol, an ox condemned to be stoned, red heifer, birds offered by a person cured from tzaraat, hair of a nazir, firstborn male donkey, a piece of meat cooked with milk, Yom Kippur goat sent to Azazel, and unconsecrated animals slaughtered in the Temple Courtyard. All these, mixed with any amount of similar items, make the whole group prohibited.
Art: Albrecht Durer - Self-Portrait at 26