Roman mosaics for villa reconstructions — part 3; Getting the tesserae

Getting the tesserae

Now you know what you can show and why you should get a mosaic floor in progress for your villa before you go any further you need to establish one thing; tesserae, how you are going to get enough for the project. Do not do anything else as this is the one thing that will determine if you can make this a reality.

There are quite a few options and I will go through as many as I can think of. First what sort of tesserae do you need? I am not going over using modern materials, this will be easy enough for you to work out by going to mosaic suppliers for this. This is solely about getting marble/stone tesserae.

The average size of tesserae in a Roman mosaic was 10mm (3/8”) square. They were, obviously, hand cut so they were slightly irregular and the edges might be anywhere between 8mm — 12mm but they still conformed to this average size. With the material we have now it is all cut by machine so the tesserae are exact squares. Whilst not impossible to use these can give the mosaic a very flat, and what I term, ‘industrial’ look. The best option then is to get something that can be finished in the way you want.

For nearly all of the following you will need a hammer and hardie (H&H) set to cut. Any marble over 6–7 mm will need ot be cut with these to avoid over stressing your wrist. Unless otherwise stated we are talking of marble that is 10 mm thick.

Hammer & hardie in use today

Keep in mind you need approximately 24 kgs per sqm.

All prices are estimates from February 2018 and are in GBP

1. Hand cut ready to use. Get someone to supply you with hand cut tesserae. This will be very expensive and I do not know of anyone who does this.
2. 20 mm squares. Get these and then use a H&H to cut into four. You can slightly off set your cuts and this will make the tesserae slightly irregular. Not ideal, expensive and hard to find but a good, quick way. Very few suppliers, all from the same source. Retail price is £20 per kg but it can be cheaper if you get a trade account.
3. Rods. This is the best overall way, this is where marble tiles are pre cut for you into long strips. You need them to be 10 mm thick and, ideally, 20 mm width and they will be about 300 mm / 12” long. If you are getting a supply like this and you can request the cutting widths then ask if you can get them in a mix of 8 mm, 10 mm and 12 mm width. That way they will have a more irregular finish. Instead of the 8 mm and 10 mm widths you may find it more practical to ask for 16 mm and 20 mm widths. This way you can cut these into 10 mm pieces and then in half so they will be more irregular. It will also avoid too many breakages in both cutting and transport. About £8 — £12 per kg.
4. Electric wet saw to cut your own tiles into rods. A very good way ot save money. The wet saw will cost about £300 and it is very noisy and messy to operate but you then just get marble tiles from a tile store and this can take the cost of the rods right down as you will get your tiles for about £15 — £40 per square meter. If you have a member of staff or volunteer to operate the saw (very easy to learn) then the cost will be about £1.30 — £2.00 per kg (+/- £300 for the saw).
5. Hammer and hardie plus full size tiles from a tile store. Buy the tiles from your tile store at the prices estimated above, sit someone down with the H&H and get them to turn the big tiles into small tesserae! Not the most stimulating of jobs and I speak as someone who has cut 24,000 tesserae for one job like this. Not particularly practical but it can be done. As a benchmark it takes me about 40 minutes to cut a 300mm square tile into tesserae and I get about 2.2 kg from that. Cost £1.30 — £2.00 per kg

So this gives you a rough idea of the costs involved in the tesserae. It may seem expensive but if you bear in mind that you can start a small display in a corner of a room which may need only 5–10 kgs of material.