It's about as heavy as a Grand Piano.
(for Steinway & Sons, Model D Concert Grand Piano)
It's about one-and-one-tenth times as heavy as a Horse.
In other words, the weight of a Horse is 0.91 times 450 kilograms.(Equus ferus caballus) (Arabian, adult)
n Arabian riding horse (or similar breed) weighs between 380 and 450 kg. During races, horses must carry jockeys and their equipment, which in the Kentucky Derby, for example, can weigh up to 54.4 kg.
It's about nine-tenths as heavy as a Polar Bear.
In other words, 450 kilograms is 0.872 times the weight of a Polar Bear, and the weight of a Polar Bear is 1.15 times that amount.(Ursus maritimus) (adult, male)
It's about nine-tenths as heavy as a Grizzly Bear.
In other words, 450 kilograms is 0.864 times the weight of a Grizzly Bear, and the weight of a Grizzly Bear is 1.16 times that amount.(a.k.a. brown bear, a.k.a. silver bear, Ursus arctos horribilis) (Adult, male, coastal area population average)
It's about four-fifths as heavy as The Heart of a Blue Whale.
In other words, the weight of The Heart of a Blue Whale is 1 times 450 kilograms.(Balaenoptera musculus) (adult)
It's about two-thirds as heavy as a Cow.
In other words, the weight of a Cow is 1.5 times 450 kilograms.(for Holstein, a.k.a. Holstein Friesian, a.k.a. Friesian, Bos primigenius) (adult, heifer)
It's about one-and-four-fifths times as heavy as a Pig.
In other words, the weight of a Pig is 0.56 times 450 kilograms.(Domestic pig, Sus scrofa domesticus, a.k.a. S. domesticus) (adult)