This is the story of how marble gets from deep underground to you. That is, if you happen to use marble a lot.
I have always wanted to see a marble quarry in action after having seen photos of them and so it was serendipity when, after booking a touring holiday of central Portugal, and researching what there was to see at each of our stays, I discovered that our stay at the Pousada of Vila Viçosa was slap bang in the centre of the Portuguese marble industry. Not only that but there was a guided tour offered by a local marble company which coincided with our stay in the town.
Vila Viçosa is the home of Portuguese marble and has been since Roman times. The tour started in the local company office in their small exhibition room and this model below gave some context to where we were going. The deepest marble quarry in Portugal.
On the way to the town and from there to the actual quarry we were driving through the geological region of the "Entremoz Anticline", and these waste tips, below, were a common sight. The nature of marble means that much of what is quarried is rejected.
The Estremoz Anticline is one of the great marble extraction sites in the world. The excellence of these stones is evidenced by their chromatic diversity and physical and mechanical properties, established by the increasingly specific demands of international markets, placing the Estremoz marble stones among the best in the world.
The making of marble starts with limestone which is formed from both calcium deposited from water borne sediments or directly from the deposit on ocean floors of corals or shells. This limestone is then buried several kilometers deep underground as the continents move. In this case 250 to 550 million years ago, when the limestone endured immense pressure and heat which turned it into the "cooked" marble we see today. Of course we had to wait hundreds of millions of years for it to come back to the surface here in Portugal. During that process other minerals fall into the cake mix of marble, and just like marble cake, leave their streaks and swirls of colour throughout the white stone giving it it's beauty and unique qualities.
The quarry site is a dramatic sight.
Here is a small picture of me, falling off the edge of the quarry in my nightmare. It's a long way down. Perigo means danger. I know because I am from Wales and the word for danger there is Perygl. My assumption that Queda means fall and Altura means from a very great height, turned out to be correct too. The picture helped.
We started off in the cutting area and this is the machine that does it. Everything related to marble is big and dusty and rusty and highly dangerous, which is why we were wearing High Visibility tops and hard hats although I am fairly sure a hard hat would not survive the impact of a two ton block of marble.
The thin black line behind the stone in the middle is the cutting blade. It is a flexible saw blade of synthetic diamond.
This is what a used one looks like.
This is us in our hard hats. The bed of the machine where the crane operator is standing is made of marble. Nearly everything in the area is made of marble.
This was our first sight of the large hole. The darker top layers were dug out by the Romans 2000 years ago. By now they look just like normal weathered rock. The fresh blocks of new white marble are stacked up all around the site.
This is a composite shot of about 8 photos. The hole is so big that you cannot get it into a single shot. This doesn't even show the deepest part of it.
Click on this photo if you have a large screen and want to see more detail.
This is 40 Bank Street, London and it would fit in the hole with room to spare.
The water at the bottom has to be pumped out continually or this would be a very large water feature.
As I said, it is a very long way down.
If you look closely, there are people down there.
Next we had to drive to the factory, where the magic happens. By now our hire car was coated in marble dust and the car park is of course lined with sheets and blocks of marble. Note that white patterned sheet of marble at the back. If you slice marble and open it like a book you get a mirror image.
Here are the rough hewn blocks fresh from the saw we saw earlier. Thats a good use of homonyms right there. Two words with totally different meanings that look and sound identical. You know me, I have to throw things like that in, just when you are getting comfortable.
There are many different patterns and colours, often coming out of the same quarry. When cut, the stones are photographed and coded. This means when an architect arrives to choose their marble, particular types are easier to find.
The slices from a single block are kept together.
This references the waste I mentioned earlier. The minerals that add pattern and colour, can also add weakness if they are not thoroughly mixed during the transformation process. If not perfectly formed it can lead to cracks or weak spots.
This is a very particular type of marble right here, and a splash of water reveals the colour and pattern. They are very proud of this marble and rightly so because it was used in a recent building project in New York.
Yes, it is completely covered in Portuguese marble from Vila Viçosa. This is the latest addition to the former site of The World Trade Centre.
The Performing Arts Center measures 160 by 160 feet (49 by 49 m) across and 117 feet (36 m) tall, resting upon a black-granite pedestal that measures 21 feet (6.4 m) tall. The building's facade consists of 5,000 panels of veined Portuguese marble. The panels contain lozenge-shaped patterns and turn an amber color at night.
This is one of the slicing machines which slices a single block into multiple slices in a single operation that takes place at night when power costs are lower. There is a row of these machines and they are loaded up with new blocks during the day.
The backs of the machines are made of marble of course.
Look, just one hand!
This old workhorse just moves marble around the factory. They don't make them like this anymore.
Of a slightly later date is this state of the art polishing machine which is fed with the slices of marble. The polishing is a slow process starting with course polishing pads and gradually moving down through several grades of finer abrasive pads.
These are what the pads look like and several are held in a disc which rotates across the surface of the marble.
Here are the polished sheets.
Here is the robot saw that is programmed with the sizes of the panels or tiles that are to be cut. Every operation, cutting or polishing uses vast quantities of water to keep the tools and marble cool. The water is recycled and the marble sludge filtered out and used for other products like toothpaste, paper or fertiliser. Plants love a lunch of marble dust.
Here are the finished tiles, still wet from the saw blades.
Here they are ready to be shipped out to building sites all over the world.
While back in town, next door to our Pousada is what they do locally with marble, which is pretty much cover every surface with it, including the ground beneath our feet. This is the Ducal Palace.
In 1502 the building of the Ducal Palace of Vila Viçosa was begun, sponsored by Jaime, fourth Duke of Braganza. Jaime was a skilled military leader who later led the Portuguese to victory against a Moorish army in the Battle of Azamor, in Morocco. The Ducal Palace was greatly remodelled between the 16th and 17th centuries in a sober late Renaissance (Mannerist) style, and was decorated through the centuries by several artists.
I will do a later post on the town of Vila Viçosa.
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