Quarrying in the past

The quarrying and working of granite has for years been based on rudimentary instruments and the hard labour of man.

Two important periods can be identified in the evolution of traditional quarrying techniques.

To begin with, and giving a low yield, portions of rock were isolated using wooden splitter wedges (called cugnere) hammered into natural fractures. These were then soaked in water so that they swelled up and caused the detachment of slabs which could subsequently be worked. The wooden splitters were slowly substituted by metal pins called punciotti.

By about the middle of the 19th century, a more intensive quarrying process contemplated the use of dynamite charges. This led to a high yield but vast amounts of material were also lost. The fact that most of the work had to be done by hand meant that there was always a high number of workers present in the quarry at any one time.

Transport and Processing of the Stone in the past

In the quarry, the slabs were moved and turned over using a wooden jack and derrick, anchored with cables to the rocky surrounding walls, and equipped with pulleys to reduce the force needed for lifting. If small, slabs were moved by means of wooden, metal-wheeled barrows or they were carried in wooden gaskets.

Before the advent of heavy goods vehicles and caterpillars with combustion engines, transport down the valley was carried out by fastening the squared-off slabs onto a wooden chassis and sliding them along long, paved slopes called vie di lizza.

For quarries at high altitudes, cableways with wooden platforms and metal cables were used.

In more recent times, tracks with special wagons intended to keep the material in horizontal position were introduced.

On the valley floor, the main means of transport was by a strong, reinforced cart which had a slightly sloping bottom and was pulled by oxen or horses. The slabs were then loaded onto boats and, following the water-courses, could travel long distances to reach their various destinations.

In the Quarry today

From the beginning of the 20th century, when mines fell into disuse, there was a further development in quarrying techniques which led to the present-day situation that can be defined as both rational and regularized, involving a high degree of automation, high productivity in terms of useful material extracted and a lower level of risk.

The advent of pneumatic perforators and machinery has led to an industrial type of process. The pink granite quarries of Baveno are opencast, the most common type of quarry for ornamental stone; cutting takes place in a regular way, starting at the top and cutting downwards in steps that correspond to the quarry face and trace a series of inclined surfaces on the slopes.

The mass of rock which is detached from the deposits is called a “bancata” (bench) and, although it can vary in volume, it is generally of standard and commercial dimensions. This is then sectioned and divided into slabs and blocks that can be easily transported by truck; in the quarry, the slabs are moved by means of machinery (excavators, shovels or derricks). Transport too, since the start of the 20^th century has been by road.

Cutting and rough-hewing today

The processes of cutting and rough-hewing are still carried out using a blade, mounted on pneumatic perforating equipment. First, a series of parallel vertical holes are drilled (the so-called continuous cutting process). Then, a light explosive is attached to a detonator so as to provoke a controlled explosion. Next, perforating machines working on tracks drill horizontal holes that cause the total detachment of the blocks. This saves a considerable amount of time compared with the past and, with only minimal quantities of explosive, large blocks can be cut.

As an alternative to explosives, the technique of diamond-wire cutting may be used: this is a steel cable covered with synthetic diamond beads that exploit the typical abrasive and cutting effects of this mineral on all others. The wire is on a cutter mounted on a rack support: as the cutting process proceeds this moves away from the quarry face maintaining a constant tension in the wire so that it cuts into the rock.