Researchers believe they have found Leonardo Da Vinci's "sorrow stone" - a creepy, miniature skull crafted in great anatomical detail.
Missing a lower jaw, the early 16th century artifact was found by a German couple in 1987 in an antique shop.
"It is a small, naturalistic looking, deformed skull of a more than 50-year-old-male and it is made of a partially hollowed stone like material," wrote independent Belgian researcher Stefaan Missinne in the Wiener Medizinische Wochensschrift, a medical journal published in Vienna.
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Milky white with small, brownish-yellow stains, the tiny artifact features remarkable detail. "Detailed eye sockets lead to the inside of the cranium and allow for a ‘view' of the inside, which is anatomically abnormal," Missinne said.
According to French skull expert Roger Saban, the object resembles an anatomic drawing known as RL 19057. Housed in the Royal Collection in Windsor Castle, the unpublished drawing shows a similar deformed skull missing a lower jaw.
Despite the extraordinary level of detail, the drawing and the skull both feature the same small anatomical errors, further strengthening the link with Leonardo.
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Chemical analysis showed the artifact was made from an agate-based mixture of quartz and gypsum. Leonardo invented this mixture, which he called "mistioni," between 1503 and 1509. No one else is known to have experimented with this material, which was likely sourced in a mine near Volterra in Tuscany.
The size of the artifact match Florentine measurement units that were used in the Renaissance. "The origin of the skull, leads, therefore, to Florence," Missinne said.
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Contemporary writings such as those in the inventory of Da Vinci's assistant Salai confirm Leonardo's possession of a detailed miniature skull made from mistioni.
The skull dates to about 1508, Missinne said, when Leonardo was 56. Missinne believes the aging artist, who was prone to being melancholic, used the skull as his personal sorrow stone.
"The skull was exhibited several times, the last being in Leoben, Austria, and not one negative reaction was expressed on its attribution to Leonardo," Missinne said.
Photo: The miniature skull attributed to Leonardo Da Vinci. Credit: Dr. K.Becker