Hi @Simon_Daw - I would suggest both a materials table and a suppliers table. Keep the materials and its attributes/uses together and have a linked field to make the link to the suppliers table.
If multiple suppliers supply exactly the same product then your linked field could contain one or more suppliers. If the materials are similar but different by supplier, then I think you would have a material record per supplier (and, again, linked to the supplier).
You might also find there are opportunities to normalize your data more. If, for example, there are some common uses, you could make the “uses” field a single select (dropdown) or even a table in its own right (with a linked field to the materials table).
If this answers your question, please consider marking it as the “solution”. If not, please post again for more help. Thanks!