Marble Processing

Marble processing is a fascinating art.

From the quarry and until they are loaded onto containers ready for shipment, marble slabs go through different transformation phases. Depending on the needs, each block of marble is cut in slabs or as per the required measures in order to build staircases or to be used in flooring, wall tiling, etc.

Processing stages

1. Marble mining
2. Arrival and unloading of marble blocks
3. Marble cutting
4. Strengthening and polishing
5. Slab storage
6. Loading

 

First stage of marble processing: Mining

 

Nature is in charge of providing marble with its shape and colour for thousands of years. Therefore, this is always a unique, rare material.

Mostly composed of calcium carbonate, marble has been and continues to be used as a construction and decorative material, due to its beauty and resistance.

Marble is currently being obtained from open cast quarries such as Crema Marfil Coto. But also from underground quarries.

Extraction methods and the resulting marble block sizes will depend on the quarry in question. Marble quarrying is usually done in vertical cuts. However, there are also cases where it is also done in horizontal cuts. This shall depend on the area’s morphology.

 

 

The resulting block comprises 6 parallel sides. Each of these sides weighs between 6 and 15 tonnes. In regards to dimension, it can be between 2.2 and 3 metres. Width can also be 1.2 to 1.5 metres, with 0.9 to 1.2 metres in height.

 

 

Block classification

Once each block is extracted from the quarry, these are classified based on certain quality criteria, such as:

• Block size
• Tones
• Amount of streaks: the lower the amount of streaks, the higher quality and better classification.
• Cleanliness: clean materials are those with no stains
• Cracks

As a matter of example, a top quality Crema Marfil marble block would be a lighter colour tone with almost no streaks.

Depending on how each block is classified, this will determine the marble’s price.

 

Arrival and unloading of marble blocks

 

Once the blocks have been extracted from the quarry, these are transported by HGV lorries to the manufacturers for processing. At each production centre, the blocks are unloaded and classified in the blocks yard prior to being sawed.

Due to their large dimensions and heavy weight, the blocks need to be moved and handled with cranes and specific machines, both during loading/ unloading and during processing.

Blocks are generally stored outdoors in the block yard until the next phase: the marble processing phase.

 

 

 

 

 

 

Marble cutting

 

Marble is cut using multiwire or block cutters. Depending on their dimensions, blocks may be cut using different methods, i.e., large blocks will be processed in the multi wire cutter, while smaller, irregular blocks will be cut using block cutters. The aim is to make the most of the block’s measurements by reducing any waste as much as possible.

Other features such as the type of marble, quality, required materials (slabs, tiles or staircases) shall also influence the choice of block to be cut.

Multiwire cutters will produce slabs. On the other hand, block cutters will produce strips that will be subsequently processed by the mitre saw or cutter in order to create tiles.

Slabs have a maximum width of 1.8 and 2 metres. Their maximum thickness is 1.5 cm.

Whereas standard marble tiles have a thickness of between 0.9 and 2 cm and are available in the following sizes:

• 30,5 x 30,5 cm
• 30 x 60 cm
• 40 x 40 cm
• 60 x 40 cm
• 60 x 60 cm

 

Multiwire marble cutting

Blocks are introduced in the machine by means of a platform that simplifies their movement.

They comprise diamond wires that can cut the block in a vertical direction. In this manner, they are able to obtain as many slabs as the number of wires they are equipped with. A Crema Marfil block will usually take around 8 hours to cut.

Once the block has been sawed, the slabs are processed individually in a production chain.

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Marble block cutting

In the case of highly irregular blocks, cutting performance levels will drop and therefore, there will be additional costs. For this reason, we use block cutters instead.

Block cutters are equipped with a large diameter diamond saw blade to cut blocks in a vertical direction. These cuts are made in both directions.

At the same time, these also include a further horizontal saw blade to cut the strips once the right vertical thickness has been achieved.

Once the strips are obtained, these are processed in the cutter to obtain the desired measurements.

 

 

 

Marble strengthening and polishing

 

Slabs are taken to the production line for further processing. As a first step, the material is strengthened by attaching a mesh for further resistance.

Following, the marble is subject to an abrasion process in order to change its appearance and to produce different finishes:

• Polishing: in this case we enhance the marble’s shine and colour by leaving a smooth, glossy surface. Polishing time will vary depending on the block dimensions. It can usually take between 45 and 60 minutes.
• Honing: consists of achieving a matt, shine free surface. Its main difference with the raw marble is that this finish removes all cutting marks.
• Ageing: this finish provides natural stonework with a rugged, shine free aspect resembling natural wear and tear.
• Bush hammering: produces a coarser finish providing additional grip, which makes it ideal for outdoor areas.
• Sanding: This finish achieves a much less coarse surface than the bush hammering process.
• Split face: this is the most rustic finish, which can achieve a very rugged surface.

 

And this would be the very last stage in the marble preparation process in the case of slabs that are ready for sale. Otherwise, the slabs would be subject to further cutting and finishing procedures.

 

 

Strengthening and polishing of Crema Marfil marble slabs

 

Slab storage

 

Once the corresponding finish has been applied, the slabs will be ready for display or will go directly to packaging ready for shipment.

If the marble slabs are being shipped abroad, a series of wooden bundles will be prepared in order to introduce them into containers. While if your slabs are being shipped within Spain, these are transported using iron a frames to hold them in place.

In the case of destination is in the Balearic Islands, the slabs will be transported in cages.

Tiles, on the other hand, are packed in wooden boxes for transportation.

 

 

 

 

Marble loading and shipment

 

Marble attracts a great deal of interest worldwide. For that reason, you can easily find it anywhere in the world. As previously mentioned, we will use different shipment methods depending on the destination.

Among the most common means of transportation are ships, lorries and train to ensure that our marble reaches its final destination.

 

 

I’m convinced that you will find that marble preparation is a very exciting process.

In case of any queries in these regards, please do not hesitate to contact us. 🙂