Rock Technologies Loose Chalk is 100% pharmaceutical-grade magnesium carbonate. It comes in a 100% recyclable paper package, roughly broken up climbing-specific magnesium carbonate, perfect for highly active climbers who want the best chalk. 
100% pharmaceutical-grade magnesium carbonate, RT's own formula mixed and packed in the UK, gives superior drying and friction qualities and doesn’t contain any artificial drying additives.

Features - 

• Pharmaceutical grade for quality and performance
• 300g recyclable  paper bag
• Fine texture for those who like a powdery feel to their chalk
• Plastic Free
• Made in the peak district.