It's about one-eight-hundred-fiftieth as heavy as The Space Shuttle
In other words, the weight of The Space Shuttle is 830 times 3,000 ounces.(for Endeavour, a.k.a. OV-105, a.k.a. Orbiter Vehicle-105) (empty weight, excluding main engines)
When empty, the space shuttle Endeavour weighs 2,500,000 ounces. The shuttle's spacious cargo bay carried the Chandra X-ray Observatory into orbit in 1999 — a payload that weighed 700,000 ounces.
It's about 900 times as heavy as a Deck of Cards
In other words, the weight of a Deck of Cards is 0.0011 times 3,000 ounces.(ISO 216 B8 size, a.k.a. "poker size" 63 x 88 mm, 52-card deck)
A deck of 52 ISO 216 B8-size playing cards weighs 3.30 ounces. Utilizing nearly 3,700 decks, the record-holding largest card tower was built in early 2010, stood over 3.5 m (11 ft), and weighed over 8,000 ounces.
It's about one-one-thousandth as heavy as a Blue Whale
In other words, 3,000 ounces is 0.000814 times the weight of a Blue Whale, and the weight of a Blue Whale is 1,230 times that amount.(Balaenoptera musculus)
Blue whales weigh between 3,690,000 ounces. The largest mammal to have ever lived, blue whales feed almost exclusively on krill — tiny invertebrates weighing about 0.0353 ounces each.
It's about 1,500 times as heavy as a Battery (C)
In other words, the weight of a Battery (C) is 0.00077 times 3,000 ounces.(Alkaline)
A "C" size battery weighs 2.30 ounces. C batteries are typically used in medium-drain devices such as musical instruments.
It's about 1,500 times as heavy as a Tennis Ball
In other words, 3,000 ounces is 1,470 times the weight of a Tennis Ball, and the weight of a Tennis Ball is 0.00068 times that amount.(ITF Standard; for Type 2 ball)
Per International Tennis Federation standard, regulation tennis balls must weigh about 2.04 ounces. Competition balls are also tested for bounce height, with the standards requiring that a ball dropped from 254 cm must bounce back to a height of 135 cm to 147 cm.
It's about one-two-thousandth as heavy as a House
In other words, 3,000 ounces is 0.000545 times the weight of a House, and the weight of a House is 1,830 times that amount.(149 sq. m, single-level, unfurnished)
A 149 sq. m (1,600 sq. ft), single-story, unfurnished house (without extensive masonry) of the type commonly found in America would weigh approximately 5,500,000 ounces, based on the weight of the included materials. In contrast, a yurt — a type of dwelling structure popular among nomadic peoples of East Asia — typically weighs less than 16,200 ounces.
It's about 2,000 times as heavy as a Golf Ball
In other words, 3,000 ounces is 1,852 times the weight of a Golf Ball, and the weight of a Golf Ball is 0.00054 times that amount.(per R&A USGA Rules of Golf; maximum rule weight)
According to the Rules of Golf (as approved by the United States Golf Association and the Rules Committee of the Royal and Ancient Golf Club of Saint Andrews), golf balls must weigh no more than 1.620 ounces. Golf balls are not required to have the familiar dimpled pattern, but the design has been popular since its invention in 1905 because it reduces drag while increasing lift.