Silver Cuttlefish Casting – An age old sustainable technique!

Have you ever heard or indeed wondered how you cast silver into Cuttlefish bone to create a fab ‘one-of-a-kind’ piece of jewellery?… Sounds cool huh!

Plus it’s an age old sustainable technique, so this month’s blog post will give you some insight as to how we do it at Julia Thompson Jewellery HQ and how you can get involved and try it for yourself!

The Common Cuttlefish, Sepia officinalis. Image credit: © Tennessee Aquarium.

The Common Cuttlefish, Sepia officinalis. Image credit: © Tennessee Aquarium.

There’s no doubt about it that Cuttlefish are amazing creatures, and when they come to the end of their lives in the ocean, cuttlebone can be widely found washed up on beaches around the world.

It is therefore a waste product and free resource that can be harnessed to create amazing three dimensional pieces of solid precious metal jewellery.

Cuttlebone has been used as a mould making and casting material by jewellers for hundreds of years.

The soft fine multiple layers of bone within the hard exterior shell can be easily carved.  It also compresses brilliantly well when an object is pressed into the fine layers, holding it’s form and shape once the object has been removed.

The bone can also withstand high temperatures such as molten silver and gold allowing a near perfect casting of the carved design or pressed in object!


How to create a Cuttlefish Bone Mould…

  1. Firstly the cuttlebone is cut in half across the width using a saw.
  2. Both pieces are then sanded flat on one side only using wet and dry paper until they fit flush against one another.
  3. The flattened sides are then ready to be carved, or for a small object to be pressed into the bone fairly near to the horizontal sawn edges.
  4. Location beads or small wooden pegs (broken off matchsticks) are then pressed into the bone around the design so that both sides of the bone marry up correctly.
  5. If pressing in an object this then has to be removed to leave the negative space free to be filled with molten metal.
  6. A pouring channel or funnel then needs to be carved from the horizontal sawn edges down to the top of the design.
  7. When sandwiched back together using the locating beads or pegs, notches need to be sawn into the sides of the mould.
  8. Finally… Wire is wrapped around and into the notches of the two sandwiched pieces of cuttlebone. It is then twisted tight and the excess cut off to create a secure mould!


One of my students Yvonne, carving a design to be cast directly into the cuttlebone.


Sandwiched & bound together with a pour channel cut ready for molten silver!


Naomi’s brilliant Medieval horse brass cast. The black horse brass above is what she pressed into the bone, and the silver one below is the outcome of the casting. Check out the charred remains!

The cuttlebone mould is a ‘one off’ and the outcome unique!

Yvonne’s finished articles. One carved and the other a copy of a pressed in object. It’s amazing how aquatic these pieces are, check out the beautiful layers on the arrow head, almost like waves, which transferred during the casting process from the makeup of cuttlefish bone!

Want to try your hand at Cuttlefish Bone Casting?

If you would like to learn more and live in the West of England, I run a fun and exclusive day course with guest teacher Rebecca Prosser where you get to experiment with hand carving a unique design AND cast an object of your choice in recycled silver scrap through the medium of cuttlefish bone.

Leave with two handmade pieces of ethical precious metal designer jewellery that you’ve made using this age old sustainable technique!

Advance booking is essential as places are limited to a maximum of 8 people thus ensuring everybody gets an excellent amount of tuition.

This was an amazing day. If ever you get chance to spend time at Julia’s workshops then do it – you won’t regret it xxxx’    Y.Froehlich

‘It’s a great experience, treat yourself next time Julia and Rebecca run the course!’    G.Carter

Click here to keep an eye on my Courses page for the next available workshop!

Silver Cuttlefish Casting

Melting the silver to pour into the prepared cuttlefish mould…


The molten silver poured in and bubbling out the top of the cuttlefish bone mould!

The molten silver post pour bubbling out the top of the cuttlefish bone mould!


If you have any questions please feel free to ask in the comments below…

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Julia Thompson Jewellery


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