Hundreds of china clay workers from Cornwall and Devon facing redundancy have taken part in a protest march.
Families joined workers as they paraded through St Austell
Imerys is cutting more than 600 jobs in both counties because it is moving its paper coating operations to Brazil where costs are lower.
About 300 people marched through St Austell, Cornwall, going through Fore Street before a rally at Polkyth.
The French-owned company said cuts were necessary. Unions claim they will take £12m a year out of the local economy.
Workers were joined by families as they paraded through St Austell on Saturday afternoon. They marched with banners protesting at the company's plans to reduce its presence in the region.
At the rally in Poltair Park, speakers include union officials from France and the United States where Imerys also operates.
Imerys is to close one of its seven china clay pits in the St Austell area.
One refinery and two drying units will also be closed in Cornwall; and a pit at Lee Moor - north of Plymouth in Devon - will also close, along with its refinery and drying unit.
The company said that it had had to make difficult decisions to secure its future in the South West.
Imerys is the largest employer in Cornwall, employing about 2,000 people.
China clay, or kaolin, has a variety of uses, but is mainly employed to whiten and give a glossy coating to paper.