Over a 3000 years of art in stone
It is a calcareous substance mined in the surrounding area that has been widely used for millennia since the Etruscan craftsmen carved it to obtain urns to keep the ashes of their dead.
Many of these cinerary urns are now exhibited in the Guarnacci Museum where the visitor can appreciate all the exquisite workmanship of the bas-reliefs. At the end of the 18th century, after a long period during which the craft of alabaster had virtually died out, Volterra saw a new Renaissance, and workshops sprang up with a high quality production that reached every part of the world, thanks to the resourcefulness of the so-called Alabaster travellers.
The secrets of the manufacture of this warm and luminous stone have been handed down for ages from generation to generation, and still represent one of the highest peaks of the italian artistic handicraft.
In the characteristic workshops of the historic centre, where everything is covered with white dust, or in the many displays all around Volterra, the visitor will find great or small masterpieces to satisfy any taste.
What is Alabaster
Chemicals and Geology
Between 26 and 7 million years ago chalk deposits were formed, material from which the white alabaster blocks come. In the early Miocene period, violent telluric movement sank the Tuscan hills under sea level.
The valleys then created were flooded with sea water and, when it dried out, the calcium sulphate that had melted with water left sediments on the bottom of the basins, creating thick layers of chalk: alabaster is a sulphate of calcium hydrate (CaSO4 – H2O).
Very slowly over time, the purest part of the chalk concentrated in homogenous and transparent spheroids while the clay impurities where expelled to the outside of the block, the dark veins are the traces left by them. Chalky alabaster quarries are also to be found in Spain, Brasil, Romania but those in Volterra are considered to have the best quality.
Types of Alabaster
Scaglione is the most common white alabaster, more or less transparent depending on the areas where it comes from. The blocks range from 30-40 kg to 10 quintals. Even huge arnioni (oval-shaped) of 25 quintals have been found. In this case, as it is impossible to extract the whole block, it is taken out in pieces, even though there is a danger that it might break internally, thus compromising the quality.
Agata is the most precious alabaster, the rarest, hardest and most difficult to work. The yellow colour can vary from a faded yellow to an intense dark yellow. A particular type of Agata, the so called red stone, is no longer extracted. The maximum weight ranges between 3-4 quintals.
Bardiglio is an alabaster with different tones, veins and colours. It usually is grey, beige or orangish and looks like marble: it is called a marble-like stone when it has veins, and Bardiglio where the colours and tones are varied. The weight of the slabs ranges from 15 kg to 25-30 quintals.
The marble-like stone (Pietra a marmo) is an alabaster with a white background with light and delicate greyish, reddish or greenish veins, like Calacata marble. Often the veins become spots.
The Cinerino or Cenerino (ash) is a grey stone, looking like clay, with a mixture of colour more or less varied and opaque. The Cinerino with a homogeneous color and mixture, that is rare, looks like a light-coloured slate. The weight of the blocks range from 20-30 kg to 4-5 quintals.
The yellow stone (Pietra Gialla) is a bright alabaster, with a more or less intense colour, sometimes almost white. It is very difficult to find. The weight of the blocks range from 20 kg to 4 quintals.
The quarries and mines
In the silence underground, footsteps are softened by dust. From time to time, there are strokes of a pickaxe on the walls, but when the resonance changes that is the right spot. As it has always been, the miner finds the point in the rock where the block of alabaster is hidden and he starts to dig it out. The miner moves the lamp closer to the oval-shaped block to control its transparency and then he starts to extract it from the clay shell in which it is enclosed.
Open air or underground quarries
In the underground quarries in Castellina the layers where the oval-shaped blocks of alabaster are found are so solid that there rarely is the need to use scaffolding to keep the galleries safe. Once the alabaster is located, drills and pneumatic chisels are used to take it from its niche; sometimes in the last phases of the operation pickaxes are used. If the block is too big it might necessitate the use of explosives, though on the other hand – as the miners say – this can well ruin the block cracking it from the inside. In the neighbourhood of Volterra, instead, the blocks are at ground level and are extracted by excavators.
Alabaster in the workshops
Types and characteristics of alabaster
The stone that is traditionally worked by the craftsmen in Volterra comes from two different locations: most from the mines in Castellina (around 25 km from the town in the direction of the sea), and the rest from the neighbourhood of Volterra.
The perfectly white and transparent stone is called Castellina. It is the best quality of alabaster, formed by the thickest layers of chalk and it is used essentially for sculptures.
The other kind of stone extracted from this area is the Scaglione, characterized by extraordinary grey veins that cross the white stone without affecting its transparency.
In order to take advantage of its reflecting qualities and to highlight its transparency, the Scaglione is usually used to create lamps.
On the other hand, the alabaster blocks that come from the town have pleasant colours, whitish, yellowish, brown and red. These are considered especially precious and they are used for bases, columns or coloured details of handmade items in white alabaster.