It's about as heavy as a Human Heart
It's about nine-tenths as heavy as a Can of Soup
In other words, 0.680 pounds is 0.880 times the weight of a Can of Soup, and the weight of a Can of Soup is 1.10 times that amount.(for Campbell''s Condensed Tomato Soup, 317.9 ml)
A can of Campbell''s Tomato Soup weighs 0.770 pounds. Cans have been used to store soup and other foods since their invention in 1913, but a dedicated can opener was not developed until cans began to use thinner materials — prior to that time, cans were usually opened using various blunt instruments and tools.
It's about three-fourths as heavy as a Football (American)
In other words, 0.680 pounds is 0.75034482758620 times the weight of a Football (American), and the weight of a Football (American) is 1.3327205882350 times that amount.(a.k.a. "pigskin") (NFL standard)
Per National Football League official rules, an American football must weigh between 0.8750 pounds and 0.93750 pounds. Because of NFL regulations, ceremonial considerations, and backup requirements, each NFL Superbowl requires the manufacture of 144 balls exclusively for the event.
It's about seven-tenths as heavy as a Football (Soccer)
In other words, 0.680 pounds is 0.720 times the weight of a Football (Soccer), and the weight of a Football (Soccer) is 1.40 times that amount.(a.k.a. Soccer, a.k.a. Association Football) (FIFA Law 2 specification)
According to FIFA's Law of the Game number 2, a football must weigh between 0.90 pounds and 0.990 pounds. An artifact on display at the Smith Art Gallery in Museum in Stirling, Scotland is said to be the world's oldest football and is about one-third to one-half the size of a modern football.
It's about one-and-nine-tenths times as heavy as a Billiard Ball
In other words, 0.680 pounds is 1.89217391304350 times the weight of a Billiard Ball, and the weight of a Billiard Ball is 0.528492647058820 times that amount.(American-style, WPA specifications)
Per the World Pool-Billiard Association, a billiard ball weight must weigh between 0.343750 pounds and 0.3750 pounds. According to legend, the difficulty in obtaining elephant ivory for the manufacture of billiard balls in the 19th century inspired the search for a replacement material, which led to the development of the first industrial plastic.
It's about one-and-nine-tenths times as heavy as a Puck (Hockey)
In other words, 0.680 pounds is 1.89217391304350 times the weight of a Puck (Hockey), and the weight of a Puck (Hockey) is 0.528492647058820 times that amount.(Ice hockey)
A standard ice hockey puck weighs between 0.343750 pounds and 0.3750 pounds. Hockey pucks can be shot or passed at speeds of up to 160 kph (99 mph) during games.
It's about two times as heavy as a Hamster
In other words, the weight of a Hamster is 0.50 times 0.680 pounds.(for Syrian hamster, a.k.a. golden hamster, a.k.a. Mesocricetus auratus; adult)
An adult Syrian hamster has a typical weight of about 0.40 pounds. Known for transporting food in the pouches of their cheeks so that they can bury it later, some hamsters can store up to 60 pounds of food in their borrows.