It's about as heavy as a Die (Dice).
(for six-sided, 16 mm, rounded cube)
It's about four-fifths as heavy as a sheet of Paper.
It's about seven-tenths as heavy as a Quarter.
In other words, 4,100 miligrams is 0.7231 times the weight of a Quarter, and the weight of a Quarter is 1.383 times that amount.(United States quarter-dollar coin) (a.k.a. Quarter dollar, a.k.a. America the Beautiful quarter, a.k.a. two bits)
It's about one-and-three-fifths times as heavy as a Penny.
In other words, the weight of a Penny is 0.63 times 4,100 miligrams.(United States) (formally one-cent coin) (Union shield design, 2010-present)
It's about three-fifths as heavy as an Eye (Human).
In other words, 4,100 miligrams is 0.58 times the weight of an Eye (Human), and the weight of an Eye (Human) is 1.7 times that amount.(adult)
A fully developed eye (in a person over the age of thirteen), weighs about 7,100 miligrams. The pupil of the eye varies depending on the amount of light it is exposed to, but typically measures about 4 mm across.
It's about two-and-a-half times as heavy as a Playing Card.
In other words, the weight of a Playing Card is 0.43 times 4,100 miligrams.(ISO 216 B8 size, 2.5" x 3.5")
A single ISO 216 B8-size playing card weighs 1,800 miligrams. Although this size is the most common home playing card, many casinos use "bridge size" cards — 2,640 sq. mm (4.036 sq. in) smaller in area.
It's about three times as heavy as a Paper Clip.
In other words, 4,100 miligrams is 2.9 times the weight of a Paper Clip, and the weight of a Paper Clip is 0.34 times that amount.(average)