Chiaramonti, both of whom published their own scathing counter-attacks on Liceti's views. Liceti was also involved in a friendlier astronomical debate with Galileo between 1640 and 1642. In 1640, Liceti published Litheosphorus, sive De lapide Bononiensi lucem in se conceptam ab ambiente claro mox in tenebris mire conservante, a work which examined the so-called “light-bearing stone of Bologna.” This stone was a type of barite originating in Mount Paderno near Bologna. The stone had the unusual property of becoming phosphorescent during the process of calcination, but it was believed at the time that the phosphorescence was caused by the stone absorbing and then gradual releasing sunlight. Liceti used this stone as analogy for the moon, believing that the moon released light absorbed by the sun, contrary to Galileo's argument in Sidereus Nuncius that the moon's illumination is caused by the reflection of sunlight from the earth. Liceti sent a copy of his book to Galileo, who, in response, wrote a polemical letter to Prince Leopoldo de' Medici of Tuscany defending his views; this letter is the last scientific work produced by Galileo before his death. Liceti complained that the letter was circulated before he had seen it so Galileo sent a friendlier version of the letter to Liceti, who published it along with his point-by-point response in 1642 as De Lunae subobscura luce prope coniunctiones, et in eclipsibus observata. In 1640 and 1641, respectively, Liceti published two more general works on light and illumination, De luminis natura et efficientia libri tres and De lucidis in sublimi ingenuarum exercitationum liber. Gemstones and Philology Liceti wrote three books on ancient gems, rings, and their hidden meaning: De anulis antiquis (1645), De lucernis antiquorum reconditis (1625, reprinted with more illustrations in 1652 and 1662), and Hieroglyphica, sive Antiqua schemata gemmarum anularium (1653). Among his philological works is De Petrarchae cognominis ortographia, a long letter commissioned by Giacomo Filippo Tomasini and included in his 1650 work Petrarcha redivivus. Miscellaneous Between 1640 and 1655, Liceti published a series of eight books in which he answered questions on a variety of topics posed through letters by some of the most famous intellectuals of the day: De quaesitis per epistolas a claris viris responsa (1640), De secundo-quaesitis per epistolas a claris viris responsa (1646), De tertio-quaesitis per epistolas a claris viris responsa (1646), De motu sanguinis, origine nervorum, de quarto-quaesitis per epistolas a claris viris responsa medico-philosophica