Porphyry was well known in the ancient world (for example by Assyro-Babylonians, Egyptians and Romans) where it was used in architecture and sculpture.
The story goes that ancient Egyptians used porphyry for their pharaohs' tombs, not only because of its wonderful red colour but especially because of its hardness and resistance that made it an everlasting stone.
In ancient Rome porphyry (which comes from the Greek word "porphyra", purple red) symbolised great prestige and imperial dignity. And in fact in Latin there is a specific word, "Porphyrogenitus", referring to someone who is "born in the Purple Chamber" (a room whose walls were covered with porphyry), which existed only in rich and noble houses.

Porphyry column (relief) representing Diocletian and Maximilian
(Rome, Biblioteca Vaticana, Galleria Clementina)

 
 

Several emperors had their sarcophagi made of porphyry and of this material were also several "rote" which decorated the floors of imperial palaces (an example of those is still to be seen in the old St Peter's Basilica)
Also the sarcophagus where rests Napoleon I under the dome of the "Hotel des Invalides" in Paris is made up of this beautiful stone, which in ancient times (until 500 AD) came almost only from mines in the Egyptian desert.
The story goes that also the tombs of Nero and Settimius Severus were made of porphyry and that parts of the imperial palaces of Diocletian and Constantine were covered with it.
The porphyry coming from Roman ruins was later used to build the sepulchral monuments of the Sicilian kings (to be seen in Palermo Cathedral). And the baptismal font in St Peter's Basilica in Rome is the porphyry slab that covered the tomb of Otto II restored and modified in the XVII century.
Even in Dante's Divine Comedy we can find a reference to porphyry, the stone covering the stairs which climbed up to the Mount of Purgatory: "The third, that uppermost rests massively, Porphyry seemed to me, as flaming red as blood that from a vein is spirting forth" (Purgatory, IX, 100-102).

In more recent times porphyry was used (where available) mainly as building stone and later on, in thin and roughly worked pieces, as roofing tiles. Thanks to its numerous qualities - resistance to all weather conditions, freezing and thawing, rain and snow and its particular stratification which makes its extraction easier - porphyry was particularly suited for those uses.

Example of a roof covered with porphyry (still used)

Only at the beginning of the XX century, porphyry (cubes, irregularly shaped tiles, cobblestones) began to be used to pave roads. One of the firsts was the "Gardolo-Albiano-Lases" in the Trento area, where also kerbstones, wayside stones and embankment walls were made of porphyry. The first real concession to extract porphyry was given in 1911.
After the First World War the extraction of porphyry began again, although sporadically, and only in the Twenties it took the form of a real exploitation.

Mines were opencast and had a front between 10 and 50 m. Porphyry was extracted using wooden or metal levers inserted into its typical stratifications (called "lassi"). Explosive was used only rarely.

Detail of typical porphyry stratifications

The material was then sorted out according to the size and thickness of the slabs and brought by means of wheelbarrows, handcarts or mule towed carts to the so called "workbenches", where other workers processed it into cubes, tiles, binders and coarse tiles.

Hand-work in a old picture.

The final product was then sent by mule-towed barges to Trento train station and shipped to its final destination. The porphyry cubes used to pave "Via Nazionale" in Rome and the central station in Milan were produced this way.

Only in the sixties local communities in the "porphyry area" around Trento realised that porphyry could become a very important source of revenue and accordingly porphyry production increased dramatically, also boosted by the economic boom of those years.
The seventies, though, were the real turning point in the production of porphyry. New machines began to be used in the extraction as well as in the processing of porphyry (pneumatic hammers, lorries, etc.) and new extraction techniques were implemented which were more suitable for meeting the increasing demand. At the same time, the research for new markets (in Germany, Austria, Switzerland and France) went on.

In the eighties the first high technology machines were introduced so as to enable the porphyry sector to deliver new products with a higher value added .

Detail of a modern machine to cut porphyry slabs

A new era has just begun and new scenarios will certainly open. A different attitude to management and the effort to offer new and high quality products are necessary to survive in a globalised world rich in new perspectives (and challenges), which were difficult to imagine even in the nineties. But our company, which has been among the leading ones since the Sixties, is looking confidently towards new challenges

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