Sources : Lynx

Ovid [1st century CE] (The Metamorphoses, Book 15, 391-417): Vanquished India gave lynxes to Bacchus of the clustered vines, and they say that whatever their bladder emits, changes to stone, and solidifies on contact with air. - [Kline translation]

Pliny the Elder [1st century CE] (Natural History, Book 8, 28): The lynx, which has the shape of a wolf and leopard's spots, was first displayed in the games of Pompey the Great (55 BC). (Book 8, 30): Ethiopia produces lynxes in great numbers. (Book 8, 57): The urine of lynxes solidifies into drops like carbuncles, colored like flame; this substance is called "lynx-water" (lyncuriam). Lynxes know that this happens, so they cover their urine with earth to make it solidify more quickly.

Aelianus [170-230 CE] (On the Characteristics of Animals, Book 4, chapter 17): The Lynx too hides its urine, for when it hardens it turns to stone and is suitable for engraving, and is one of the aids to female adornment, so they say. - [Scholfield translation]

Gaius Julius Solinus [3rd century CE] (De mirabilibus mundi / Polyhistor, Chapter 2.38): The urine of the lynx is said to collect and harden into precious stones by those who have narrowly investigated the nature of stones. That this is known to the lynxes themselves is proved by this example: when they discharge liquid, they immediately cover it, as much as they are able, with hillocks of sand. No doubt they do this from spite, lest such matter as issues from them be useful to us. As Theophrastus holds, these stones are the colour of amber. The substance attracts by a breath things that are near at hand. It cures diseases of the kidneys and assuages the jaundice; it is called luncurium. - [Arwen Apps translation, 2011]

Isidore of Seville [7th century CE] (Etymologies, Book 12, 2:20): The lynx is said to have its name from the Greek lukos because it looks like a wolf (lupus), though its back has spots like a pard. The urine of a lynx hardens into a precious stone call lynx-water. Due to a natural jealousy they do not want humans to have the stone, so they cover their urine with sand to hide it.