In the Talmud and the Midrashim there are many references to Shamir—unusual qualities were ascribed to it. For instance it reportedly could disintegrate anything, even hard, durable stones. The rabbinical literature describes it as being employed in engraving the breast plate of the High Priest. Among Solomon’s possessions it was the most wondrous. King Solomon was eager to possess the Shamir because he had heard about it from earlier days; knowledge of the Shamir is in fact ascribed by rabbinical sources to Moses. After much search a grain of Shamir the size of a barley-corn was found in a distant country, in the depths of a well, and brought to Solomon. But strangely, it lost its abilities and became inactive several centuries later, about the time the Temple of Solomon was destroyed by Nebuchadnezzar.

What was Shamir?

In the opinion of medieval authors, Rashi, Maimonides and others Shamir was a living creature, a worm.1 It was argued that Shamir could not have been a mineral because it was active. The Talmud transmits in the name of Rabbi Nehemiah the following description of the engraving on precious stones: The names of the twelve tribes were inscribed on the twelve semi-precious stones of the Urim and Tummim, the breastplate of the High Priest, not by carving, but by writing with a certain fluid and “showing” them to Shamir, or exposing them to its action. In the opinion of modern authors, the expression “was shown to Shamir“clearly shows it was the glance of a living being which effected the splitting of wood and stones.”2 It is admitted, however, that “in the Talmudic-Midrashic sources it is never explicitely stated that the Shamir was a living creature.”3 An old source. The Testament of Solomon, a work written in Greek, probably in the early third century of the present era,4 refers to Shamir as a “green stone.” But how could a greenish stone cut the hardest of diamonds with its glance?

“The Shamir is as large as a barley-corn. It was created in the six days of Genesis. There is no substance hard enough to withstand its action”5

Over a hundred and twenty-five years ago a Jewish scholar in Germany published a paper to prove that Shamir is a mineral,6 but more modern authorities agree with the medieval rabbis and say that they were “undoubtedly correct.”7

The manner in which Shamir was kept secure may give us some clue “The Shamir may not be put in an iron vessel for safe-keeping, nor ii any metal vessel: it would burst such a receptacle asunder.”8 “It is kept wrapped in wool inside a box of lead filled with barley-bran.” This sentence is quoted from the Tractate Sotah 48b of the Babylonian Talmud. “Oferet in the text is properly translated as “lead.” It contains an important clue: folkloristic fantasy would not make a leaden box of a greater resistance than an iron or a gold one: lead is a son metal. Therefore, this must be a description based on fact. And with the knowledge of our age we may easily guess who or what was Shamir: It was a radioactive substance; radium salts, for example, acting upon certain other chemical substances, can emit a luminescence with a yellow-green hue.

The breastplate of the High Priest was engraved in the following manner. The letters were written with ink, and the stones were exposed, one after another, to the “glance” or radiation of the Shamir. This ink must have contained powdered lead or lead oxides.9 The parts of the stones which were unprotected by lead were disintegrated without leaving any dust particles which, according to the Tractate Sotah 48b, appeared especially wondrous. Those parts protected by leaden ink stood up in relief on the surface of the gems.

The most precious possession of Solomon, his Shamir, did not survive With time it became inactive. The usual version of the story—the Shamir “disappeared,” does not correspond to the Hebrew text. The word batel used to describe the end, or demise, of Shamir10 has only one meaning: “To become inactive.” Therefore, when occasionally it is said that the Shamir “vanished” at about the Temple was destroyed, this is incorrect.11 The Hebrew term for a paralyzed member is ever batel; a loafer is batlan; inactivity is batala; all these words come from the root batel. In the four hundred years that passed from the building of the first Temple to its destruction by Nebuchadnezzar in -587, a radioactive substance could become inactive.12

In 1896, one year after Wilhelm Konrad Roentgen of Wuerzburg discovered X-rays, Antoine Henri Becquerel, son and grandson of the great physicists, discovered radioactivity by accidentally placing a photographic plate near a uranium salt.

Uranium at ordinary temperatures emits an invisible radiation which resembles X-rays, and can affect a photographic plate protected by a thin layer of metal.

Marie and Pierre Curie, led by the conviction that in the midst of pitchblende, their source of uranium, there must be still another element of a much greater radioactivity, dedicated themselves to its isolation and in 1898 they succeeded in bringing forth the new element as its bromide salt-radium.

A new era in physics began with these discoveries. And because of the dramatic circumstances under which the Curies pursued their goal—and the story of the illuminating substance they found one evening when they came to their cold and poorly-equipped laboratory—the last of the three discoveries, radium, captured the imagination of people everywhere.

Radioactivity is used in the treatment of neoplasms, while the destructive work of the uranium bomb thrown on Hiroshima also goes back to the discoveries of Roentgen, Becquerel, and the Curies.

Uranium and radium are elements—the original substances of which the universe is built; they were discovered, not invented. Therefore they were present in nature since the beginning; and since radioactive elements have a limited life-time because of disintegration through radioactivity, there must have been more radioactive elements in the past; and actually, a “radium clock” is used to measure the age of rocks. Radium itself is continuously decaying, yet continuously being replenished from the decay of throium, of which it is a byproduct. The end result of the decay of radium is an isotope of lead. This lead differs from regular lead, and from the ratio of such lead to uranium in rocks, the age of these rocks can be determined. Lead is also the substance that protects best against the damaging effect of radium or other radionuclide irradiation; and thus laboratory radium is preserved in a lead receptacle when not in use for medical or technological purposes.

The information found in ancient sources—that Shamir was a greenish mineral, that it was as large as a barley-corn; that it could damage anything, even metals and other minerals, save lead, and the only protection could be found by placing Shamir in a leaden box; that it had a “glance” which disintegrated things without leaving filings or dust; that it became inactive after a period of four hundred years—all reveal the true nature of Shamir.


  1. Rashi, Pesahim 54a; Maimonides, Commentary on Abot 5.6.

  2. L. Ginzberg, The Legends of the Jews, (Philadelphia, 1925), vol. V p. 53, n. 165.

  3. Ibid., loc. cit.

  4. C. McCown, The Testament of Solomon (Leipzig, 1922), pp. 105 ff. F C. Conybeare (“The Testament of Solomon,” The Jewish Quarterly Review XI [1898], p. 12) dated it to ca. 100 C.E.

  5. Tractate Sotah 48b of The Baby Ionian Talmud.

  6. S. Cassel, “Ein archaeologischer Beitrag zu natur- und Sagenkunde,” Denkschrift der Koeniglichen Akademie gemeinmitziger Wissenschaften in Erfurt, (19 July, 1854), pp. 48-112.

  7. Ginzberg, Legends, loc. cit.

  8. Ibid., Vol. I, p. 34

  9. [Possibly the ink contained sugar of lead, which is the salt of acetic acid solution—a readily available reagent for the ancients, as acetic acid is the major constituent of vinegar.—F.B.J.]

  10. Tractate Sotah (Seder Nashim) 9.2.

  11. E.g., Ginzberg, Legends I. 34.

  12. Radium loses about one percent of its radioactivity every 25 years.