Le verre alchimique d’Albert au pseudo-Raymond Lulle

[Paul Ferguson]

"During Antiquity, glass is understood as a metal. Then during the Middle Ages, crushed glass is regarded as a purifying agent, necessary for the
alchemy process. It is also highly commanded as the perfect container (alembic, urinal), despite the actual use in workshops of earthenware
or metal vessels by the alchemists. But it is certainly its manufacturing process, i.e. the transformation of simple elements (sand, ashes) into
glass that seems to fascinate the alchemists. It is a model for “The Sacred Art”, the ultimate proof that the transmutation of lead into
gold is possible. Sedacer, a 14th century alchemist ranks it even as high as the philosopher’s stone."

By Antoine Calvet.

https://www.academia.edu/51436362/Le_ver...contenants

[Paul Ferguson]

More about Sedacer:
Guillaume Sedacer (Guillem Sedacer), a prominent 14th-century Catalan alchemist and Carmelite friar best known for his highly influential medieval treatises on chemistry and glassmaking. [1, 2]
Active between 1370 and 1383 under the protection of the royal house of Aragon, Sedacer is celebrated by historians for bridging the gap between practical craftsmanship and alchemical philosophy. [3, 4]

* The Sedacina: His main Latin work, Sedacina totius artis alchimie, is highly unique because its longest chapter focuses heavily on the technical recipes of glassmaking. His name itself stems from the Low Latin setacium, meaning a "sieve" or "tamis". [1, 5, 6]
* Philosophy of Glass: Sedacer famously defined glass as "a transparent body, artificially brought to the nature of quintessence," believing it was a mutable substance (lapis convertibilis) that could eventually be transformed into the Philosopher's Stone. [7, 8]
* Practical Impact: His precise chemical formulas—such as using soda ash obtained from burning coastal barilla plants—directly influenced early Mediterranean maritime technology, specifically the manufacturing of high-clarity glass used in marine sandglasses (hourglasses used for sea navigation). [2, 9]

[1] [https://books.openedition.org](https://books.openedition.org/vrin/21638)
[2] [https://en.wikipedia.org](https://en.wikipedia.org/wiki/Marine_sandglass)
[3] [https://www.idref.fr](https://www.idref.fr/069534594)
[4] [https://www.academia.edu](https://www.academia.edu/112875239/Meridies_XIV)
[5] [https://www.academia.edu](https://www.academia.edu/116707164/Glass..._Peninsula)
[6] [https://dspace.library.uu.nl](https://dspace.library.uu.nl/server/api/...92/content)
[7] [https://www.academia.edu](https://www.academia.edu/40144531/The_Al...lassmaking)
[8] [https://glassroots.co.za](https://glassroots.co.za/blogs/forthelov...-chemistry)
[9] [https://en.wikipedia.org](https://en.wikipedia.org/wiki/Catalan_navy)