Traditional Chalk for Cellulose Mordanting & Natural Dyeing
Calcium carbonate, commonly known as chalk, has long been used in natural dyeing and textile preparation. It is particularly valued in traditional cellulose mordanting, where it is used during the dunging process to help stabilise aluminium acetate and prepare fibres for dyeing.
At AppleOak FibreWorks, we offer two sources of calcium carbonate:
Blanc de Meudon (France)
A traditional, finely milled chalk widely used in textile work, natural dyeing and decorative applications.
Burren Limestone Chalk (Co. Clare, Ireland)
Collected from limestone sourced near the Burren, one of Ireland's most iconic limestone landscapes. Rich in naturally occurring calcium carbonate, this minimally processed chalk performs beautifully for dunging and textile work.
As it is collected in its natural state, occasional small stones or mineral particles may be present. If required, simply sieve before use.
Product Details
| Specification | Details |
|---|---|
| Product | Calcium Carbonate |
| Also Known As | Chalk, Blanc de Meudon, Blanc d'Espagne |
| Function | Dunging, mordanting and dyeing aid |
| Form | Fine powder |
| Suitable For | Natural dyeing, textile preparation, pigment work |
Uses in Natural Dyeing
Calcium carbonate is commonly used for:
- Dunging after aluminium acetate mordanting
- Traditional cellulose mordanting processes
- Stabilising aluminium acetate within fibres
- Madder dye baths where water contains insufficient calcium
- Pigment and colour preparation
- pH adjustment in selected dye processes
Historically, dunging often involved cow dung. Today, calcium carbonate provides a cleaner and more practical alternative while serving a similar purpose in many mordanting systems.
Suggested Usage
Dunging Bath
- 1–2 teaspoons per litre of water
- or approximately 1% WOF (weight of fibre)
- or 1–3g per litre
Stir thoroughly before use, if you are using Burren stone, double the quantity.
Calcium & Madder
Calcium plays an important role in many madder dye baths.
Where local water is naturally soft and low in calcium, adding calcium carbonate can help encourage brighter, clearer red shades.
Choosing Between Our Two Options
Both products perform well in natural dyeing applications.
Choose Blanc de Meudon if:
• you prefer a traditional textile-grade chalk
• you want a consistently fine texture
Choose Burren Limestone if:
• you value locally sourced materials
• you enjoy working with minimally processed natural materials
• you appreciate a connection to place and landscape
Join Our Free Natural Dyeing Community
Looking to deepen your natural dyeing knowledge and connect with other passionate dyers?
Start by joining our free Natural Dyers Academy community, where you'll find inspiration, discussions, resources, and opportunities to learn more about natural dyes, mordanting, fibre preparation, colour exploration, dye plant cultivation, and sustainable textile practices.
Join the free community here:
https://the-natural-dyers-academy.mn.co/share/Mz7coMI6VgbJMchB?utm_source=manual
Inside the community you'll find:
• Natural dyeing discussions and inspiration
• Helpful resources and learning opportunities
• Dye plant growing and harvesting tips
• Colour studies and recipe sharing
• Community support from fellow natural dyers
• Information about workshops, courses, and Academy membership options
If you'd like more structured learning, in-depth tutorials, workshops, and exclusive resources, you can also explore our full Natural Dyers Academy membership from within the community.
Please Note
The Burren Limestone Chalk is a natural material and may contain occasional small stones or mineral particles. Sieving before use is recommended if a finer texture is required.
For textile, craft and technical use only.
Not intended for food, cosmetic or medicinal applications.