Engineers French Soapstone Welders Chalk Sticks, Pack of 12 + 1 Holder : Amazon.co.uk: DIY & Tools
Chalk for marking steel - AES
HOMEE Natural Flat White Soapstone Mineral Thin Bulk Marker for Welders Textile Marking Tools, 27 Refills 100x10x5mm for Each Perfect for Making Removable Markings on Steel Cast Iron Fabric : Amazon.co.uk: DIY
Engineers Flat French Chalk Soap Stone Welding Engineering Marking Metal x 10 | eBay