Is blood impure or pure, and is it permissible for a butcher to pray in clothes stained with blood?

Blood is impure according to the majority of scholars, based on the verse: "and blood." Scholars have agreed that blood is forbidden and impure; it is not to be eaten or utilized. The blood that is considered impure is flowing blood (the gushing, flowing blood) that comes out of slaughtered animals, not congealed blood like in the liver and spleen, or blood mixed with meat in the slaughterhouse, or what remains in the veins. So, if a large amount of flowing blood from slaughtering gets on clothes, they must be washed before prayer. However, if the blood that gets on clothes is what is mixed with the meat of the slaughtered animal and its veins, it does not make them impure, and it is permissible to pray in them.