St Austell and Newquay MP Stephen Gilbert has called on the Government to intervene to stop a European Commission directive destroying the china clay industry.
Mr Gilbert reiterated his concerns at the Commons about the danger moves to impose a levy on by-products of the china clay industry will have on jobs.
He said up to 500 jobs in the region are at risk.
Europe is looking to revoke the Aggregates Levy Exemption, under which the industry is spared a £2-a-tonne levy on its by-products, which are sold as aggregates to the building trade.
The commission says this is “state aid” and anti-competitive, which means the Treasury must suspend the exemption from April.
Each tonne of marketable clay recovered leaves nine tonnes of other materials. In 2008, 3.5 million tonnes of aggregates derived from kaolin production were sold.
In an Adjournment Debate the Liberal Democrat MP argued the number of people employed locally in the industry has fallen from 13,000 across Cornwall and Devon to just about 900 today.
The china clay giant Imerys recently announced 70 more redundancies.
Mr Gilbert said the china clay mining industry in the UK is the fourth largest in the world, and the modern clay industry, worth £155 million per year, contributes significantly to the economy of Cornwall. It is the UK’s most valuable mineral export - second only to North sea oil and gas, he claimed.
He said: “Industrial decline and outsourcing of skilled work from Cornwall are exactly the opposite of what this Government are trying to achieve nationally and locally. Let us be clear that between 300 and 500 jobs in the St Austell area are at risk if china clay waste loses the exemption from the aggregate levy.
“I would like to reiterate my plea that the Government ensure that the European Commission is given the full facts and that ministers lobby as hard as possible to allow the exemption to continue, for good environmental reasons, for Cornish jobs and for more revenue for the Treasury.”
Mr Gilbert added: “The china clay industry is as much a part of Cornwall’s history as tin mining, fishing or farming. It remains one of Cornwall’s largest employers and is responsible for millions of pounds going into the wider economy each year.
“The industry deserves recognition from Government for the vital role that it plays in helping to support the Cornish economy, and recognition from all of us for the wider role that china clay plays in our lives.”
In response Business Minister Michael Fallon promised to investigate further and said he recognised the importance of the china clay industry to the region.
“It is inextricably woven into the industrial fabric of the Westcountry,” he said.
“Any visitor to St Austell is likely to be struck by the impressive sharp peaks known as the ‘Cornish Alps’, which dominate the surrounding landscape and represent the most visible part of a story that, as he told us, goes back some 250 years.”
He added: “The European Commission is of course perfectly entitled to ask questions about any of these levies and schemes, and we have a number of cases before it at the moment, but as a member state, we are equally entitled to respond robustly and to defend the various arrangements we have put in place.
“I am not at the moment able to give him any more information about the exact state of the investigation or the timetable involved, but I am happy to write to him as soon as I get more information.”
After the debate Mr Gibert added: “The china clay industry is a key part of Cornwall’s history and I want to see it remain a cornerstone of our future too. China clay has a vital role in our national economy."
He said he welcomed the Government's support in helping to ensure the safeguarding of the clay industry in Cornwall for next 260 years.