The two diagrams are from T. L. Heath’s translation of Archimedes’ works (The Works of Archimedes, Cambridge University Press, 1897). The top diagram is on page 28 and illustrates Proposition 21 of On the Sphere and Cylinder I. This proposition is one of a series of technical lemmas leading to Archimedes’ expressions for the surface area of a sphere (Proposition 33), the volume of a sphere (Proposition 34), the surface area of a segment of a sphere (Propositions 42-43), and the volume of a sector of a sphere (Proposition 44).

The bottom diagram is from page 306 and illustrates Proposition 5 of Book of Lemmas. It is one of three propositions concerning certain properties of a geometric figure known as the arbelos.

The background contains some of the digits of pi, sometimes known as Archimedes’ constant.

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The image of Archimedes represented on the stamp is from a bust in the National Museum of Naples, Italy. However, the bust actually is one of Archidamos III, a third-century BC king of Sparta.

Also depicted is an Archimedes screw. As is typical of such illustrations, the helical blades are not drawn properly and the way in which water is trapped in the device is incorrectly shown. The artist also has water flowing uphill as it leaves the top of the screw.

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The illustration of Archimedes is adapted from a Renaissance mosaic depicting his death. His head, however, is from the bust used in the Italian stamp above.

In the background is a diagram of a laboratory apparatus commonly used to demonstrate Archimedes' Law of Buoyancy.

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The head depicted on this stamp is the same erroneous bust of Archimedes used in the Italian and Greek stamps above. A sphere and circumscribing cylinder appear in the upper right, representing the diagram Archimedes had inscribed on his tombstone.

San Marino is a tiny independent republic embedded within Italy with a population of about 30,000.

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The image of Archimedes on this stamp appears on a Soviet postcard printed in 1957, which was based on the same erroneous bust of Archimedes used in the three stamps above. The asteroid depicted represents one officially named “3600 Archimedes” discovered in 1978.

Guinea-Bissau is a small republic on the western coast of Africa.

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The stamp illustrates a painting believed to represent Archimedes entitled "Portrait of a Scholar" by the Italian painter Domenico Fetti (1589-1624) located in the Gemäldegalerie Alte Meister (Dresden, Germany).

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   300 dpi, 430 x 700 pixels, 78K
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This stamp illustrates a painting of Archimedes completed by Ribera in 1630 and now located in the Museo del Prado (Madrid, Spain).

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   300 dpi, 378 x 430 pixels, 56K
   600 dpi, 757 x 861 pixels, 208K

This stamp honors Archimedes' Law of the Lever (Ley de Arquimedes: F₁x₁ = F₂x₂), illustrating it with a set of scales.

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   300 dpi, 512 x 347 pixels, 49K
   600 dpi, 1024 x 694 pixels, 105K