Five heads of abalone means that the weight of five abalone adds up to one catty, eight heads of abalone means that the weight of eight abalone adds up to one catty, and the rest makes no difference.
The abalone sold on the market is not weighed, but sold by one, each abalone to "head" to calculate. Each catty abalone have "2 head" "3 head" "5 head" "10 head" "20 heads" and so on. For example, 8 heads of abalone, that is, 8 abalone weight adds up to a catty; 12 heads of abalone, that is, 12 abalone total for a catty. Each catty abalone "head" the number of less expensive, that is, people usually say "money hard to buy two abalone".
Extended information:
Fresh abalone is a live abalone, in the purchase of fresh abalone, try to choose some of the more raw abalone. The color of raw abalone is darker, and the feeling is obvious when you touch it with your hand. Such as abalone body color some yellow or white, almost no survival of vitality, buy back easily die, eat up not fresh.
Reference: