File:Star sapphires and tourmaline of Ceylon (Sri Lanka) in 1786 illustration - Le saphir l'oeil de chat, et la tourmaline de Ceylan démasqués (IA LeSaphirLoeilDeChatEtLaTourmalineDeCeylanDemasques) (page 19 crop).jpg

Bound with: Explication de la planche, qui représente plûsieurs variétés de la pierre aux etoiles mouvantes, *) ainsi que sa cristallisation ; Explication de la planche, qui représente le hérisson solaire et la pierre, qui le produit / Pierre Laportorie. [Hambourg : s.n., 1786].

Of the two "Explication[s] de la planche" bound with the "Saphir l'oeil de chat", Sinkankas writes: "The two...short contributions are sometimes cited as independent works, which they may have been, but they commonly are bound up together with the [Saphir]. All are rare."-​-​Gemology by J. Sinkankas, v. 2, p. 600. 

Le saphir l'oeil de chat...: "Laporterie describes and explains the reflective light streaks observed on certain corundum gems, notably on tke [sic] star sapphires of Ceylon, with remarks on the tourmaline from that country and its properties...Ma​ny specimens [of sapphire] are described in detail, along with remarks on internal structures observed and a theory that the star stones form through a series of growth and alteration cycles as evidenced by the straight bands noted within them."-​-​Gemology by J. Sinkankas, entry no. 3780 (JSL3780).

Explication de la planche...de la pierre aux etoiles mouvantes *) ainsi que sa cristallisation​: noted in Gemology by J. Sinkankas, entry no. 3781 (JSL3781).

Explication de la planche qui représente le hérisson solaire et al pierre, qui le produit: noted in Gemology by J. Sinkankas, entry no. 3782 (JSL3782).

Subjects: Asterism (Crystallography); Sapphires--Sri Lanka; Tourmaline--Sri Lanka