Jesmonite & Terrazzo

Everything you need to know about Jesmonite & Terrazzo

Katie Blood avatar
Written by Katie Blood
Updated over a week ago

How long does the Kit last (unopened)?

9 Months

How long does the Kit last once opened I.e pigments?

9 Months

How much time will I need to make my Jesmonite creation?

Give yourself about 3-4 hours in total. This includes creating terrazzo chips and also allowing your piece to set. It’s worth noting we do advise you leave you final piece for 24 hours but unless you like watching paint dry, you won’t be needed whilst it does its thing.

This craft is a really nice project to set aside a day to do, that way you can take your time with each step and get even more creative.

How long do I need to spend on sanding my piece?

This depends on the mould you have chosen! Sanding does require a little elbow grease, especially if you are revealing terrazzo chips in your design.

If you have opted for a marbled effect on any of your pieces, you won’t need to do much sanding at all. Facepots and Shells only require the bottom to be sanded which takes about 5-10 mins.

If you’ve opted for terrazzo chips then it will take you a while longer. For coasters, tealights or trays you can spend about 1 hour sanding, but that depends on how visible you want your chips to show. The process does take time but the end result is really rewarding.

I’ve done terrazzo chips in my design, but I can’t see them?

If you haven’t yet sanded your piece, then that might be why you can’t see them. You will need to sand your design in order for the chips to show through – keep going with 80 grit sandpaper to see them.

The other option is you might not have added enough chips into your mixture. Always aim to add about 20-30% chips of your total amount and you should have enough to show through.

Can I use something else instead of baking paper when making terrazzo chips?

Yes you can! Cling film works well too, but make sure you wrap it around a wooden chopping board otherwise it can move around and you need a flat steady surface to work from.

Are all the tools (e.g. sanding paper) needed included in the Kit?

Nearly all of the tools are included in the Kit for you, so you can easily get making at home! The Kit includes plastic gloves, paper cups, mixing sticks and sandpaper for you to use. You will need to grab a couple of bits from your home -- digital scales, protective plastic sheet (like a bin liner) a bowl of water and some baking paper for the chips.

Why is my piece a different colour now that it’s dry?

Wet materials often have a more vibrant colour to them and can dull down a little once they have fully dried. To bring out a more vivid version, you can seal your piece using a small amount of coconut oil or beeswax, buffing it into the surface with a soft lint-free cloth.

I’ve scratched my piece while sanding, what should I do?

Grab your 220 grit sandpaper and go over the scratch with a small amount of water, this should smooth out the scratch nicely. When working on your sanding, always have a bowl of water handy and keep the paper and piece wet as this reduces scratches.

I have colour pigment on my clothing, how can I remove it?

Colour pigment is a form of ink, and will leave a stain on clothes. When making your piece it’s always advised that you wear an apron or an old tee and protect any surfaces around you.

What do I do if my Jesmonite mixture is too thick?

As long as you have followed the guidelines and added the correct amount of liquid this shouldn’t happen. If it does, you can simply add a little more Jesmonite liquid to the mixture and it should loosen it up. Just add about a teaspoon of liquid to start with and see how you go.

If you have left your mixture for some time, it might have begun to set and you will need to add more liquid and start to pour into your mould before it completely sets.

Is it safe for children?

All of the materials use in this kit are non-toxic and safe for people who are pregnant and children. The materials are made from natural derivatives, making them very safe to handle. It's important to note that materials used should not be ingested or inhaled. The Kit is suitable for children aged 12y+, and requires adult supervision whilst using as it is not a toy.

Is it safe to use while pregnant?

All of the materials use in this kit are non-toxic and safe for people who are pregnant and children. The materials are made from natural derivatives, making them very safe to handle. It's important to note that materials used should not be ingested or inhaled. The Kit is suitable for children aged 12y+, and requires adult supervision whilst using as it is not a toy.

How many pieces can I make?

You can make up to 9 pieces depending on the mould you choose. Each kit has a re-usable mould and enough materials to make enough pieces to adorn your home with or give as a gift to someone.

- Coaster Kit: You can make up to 5 hexagonal coasters and up to 4 round coasters

- Tealights & Tray Kit: You can make up to 3 sets - one set is 1x tealight holder and 1x tray

- Shell Kit: You can make up to 8 shells

- Facepot Kit: You can make up to 4 facepots

How long does it take for terrazzo chips to set?

Once you have spread your terrazzo chips out on your baking paper, you can leave them to set for 20-30 mins. If it’s a hot day it might be a little less and if it’s a cold day, it might be a little more. Jesmonite gets hot whilst drying, so wait until it is cold and hard to touch.

How long does it take for my piece to set?

Once you have poured your mixture into the mould, you want to allow this to set for 40-60 mins. If it’s a hot day it might be a little less and if it’s a cold day, it might be a little more. Jesmonite gets hot whilst drying, so wait until it is cold and hard to touch. Once you have sanded your piece, leave it for a further 24 hours to ensure it’s fully set.

How many moulds come in the kit?

That depends on the Kit you choose!
- Coaster Kit has 1x Hexangonal Mould and 1x Round Mould
- Tealights + Tray Kit has 1x Oval Tray Mould and 1x Tealights Mould
- Facepot Kit has 1x Facepot Mould
- Shell Kit has 1x Shell Tray Mould

Can I order additional moulds?

Yes you can! If you fancy getting a little more creative, then you can order either a Coaster Kit Mould, Tealights + Tray Kit Mould, Facepot Kit Mould or a Shell Kit Mould.

Can I use Terrazzo chips in the Shell or Facepot mould?

It's not reccomended that you include chips within these moulds as you need to sand the piece to reveal the chips and this can sand away the definition on both. However, this is your creation so if you fancy trying it out then you can!

Can I add multiple chip colours in one piece?

You absolutely can! When you're making your chips you can divide your measurements into 2 or 3 and make different colours. Doing this really makes your piece look popping.

Should I store my Jesmonite liquid and powder at a certain temperature?

You would need to store the Jesmonite powder and liquid between 5 degrees and 25 degrees. It's important to not let the liquid freeze so avoid keeping it in very cold temperatures.

Can I speed up the setting time by applying heat or cold?

It’s recommended that you leave the pieces to complete their reactions and dry naturally for the piece to be fully set. On a hot day, your Jesmonite mixture will start to set quicker so you will have a little less working time.

What is Terazzo?

Terrazzo is a style of stone work that dates back to 18th century Venice, Italy. The Venetian stone masons would place marble fragments next to each other in a mortar or concrete base. They were then sanded and polished to make the speckle pattern that we see today.

Can I wash the silicone mould?

Yes you can! You can use warm soapy water to wash your silicone mould and then you can re-use it again to make another creation.

Can I use the mould with other materials (i.e resin)?

As the moulds are made of silicone they have lots of uses. You can absolutely use them for epoxy resin.

My piece is broken -- can I fix it?

We know the feeling of heartbreak! There are a couple of things you can do to save your piece and bring it back to life.
You can place the broken piece back into the mould, make some more Jesmonite mixture and pour it into the other half. Leave it to set for 40-60 minutes. This will create a really quirky design and is a great way to salvage a broken piece.
Use the Japanese Kitsungi method! Using epoxy resin or super glue, you can stick your pieces back together. Just before the glue fully dries, add some gold dust or glitter. You’ll have a really cool design once it’s dry.

Always make sure your piece is fully set before removing from the mould. You should leave your piece to set for 40-60 minutes and it should feel cold and hard to touch.

Which colours work well together when mixed?

The possibilities are kind of endless when it comes to mixing colours. It’s great to take inspiration from nature, books, magazines, food and things we see around us as some of the best colour combinations are often right in front of us.
Often contrasting colours work really well together. For example, cobalt blue and mustard yellow, or pale minty green and a vibrant coral. Other combinations that work really nicely in Terrazzo design are graded colours so you could have a really rich yellow base, with a sunshine yellow, sherbet lemon and pale cream chips in it.

Looking for more inspiration? Why not check out our blog on this!

How much colour pigment should I use?

The golden rule with colour pigments is that a little goes a very long way. Always start with a tiny amount (one small drop) and build up to the colour desired. You can always add more but it’s very hard to adjust if you add too much too soon.

Do I need to seal the piece with anything?

Sealing is always a great option to bring out the final colours, and add a slightly water resistant finish to it. You can buff a small amount of coconut oil or beeswax into the surface of your piece using a soft lint free cloth. Start with a little amount and gradually work up.

You want the piece to absorb the oil and for there to be nothing left on the surface. You can also use furniture polish or paint a clear varnish over the top to give it a high gloss finish.

Will it break if I drop it?

Yes, treat it like a ceramic piece, it’s durable but not indestructible.

Is this the same as resin? I've been concerned using resin as it's toxic

The good news is that Jesmonite is non-toxic and super-safe to use. The ingredients are made from natural derivatives and water-based which means they are not toxic to handle. It also makes them an eco-friendly and sustainable material, so they are kinder to the environment.

Can I use my Jesmonite piece as a candle holder?

You sure can! You can use the Tealights as a holder for small candles, or you could use the coaster or tray to place candles on top of.

Can you mix the terrazzo chips into oven bake or air dry clay?

Due to the baking process that oven clay goes through, it is not recommended that you mix the two materials. Whilst you can add terrazzo chips into your air dry clay, as you do not sand it, you won’t be able to see the chips properly.

What size is the mould?

All of the moulds are different sizes! If you would like to know the dimensions, please check the product details.

Can I use my Jesmonite piece to serve consumables?

It is not advised that you use Jesmonite Terrazzo to serve food and drinks in. If your piece is not sealed, it is not waterproof and can absorb any moisture or food debris that comes into contact with it, therefore it is not advised.

What should I do if I get Jesmonite mixture on my skin?

Don't worry, this will easily come off your skin! You can wash it off with warm soapy water. We recommend using the gloves provided in the Kit when you are making, this avoids getting too messy and getting any on your skin.

Did this answer your question?