A company that manufactures synthetic diamond materials is to create 100 jobs in Shannon in Co Clare.
It is part of a €7 million investment by Element Six, which is part of the De Beers group of companies.
The investment will see employment levels more than double to 550.
Recruitment is already under way and all posts are set to be filled in the first half of this year.
Most of the positions will be in the areas of engineering, manufacturing and supply chain.
The De Beers group of companies has been operating in Shannon for over 50 years.
In 2009, the Shannon plant was on the brink of closure and cited a "high cost of operating in Ireland".
The company has since heavily invested in infrastructural projects.
The latest investment will bring to €40 million its overall spend in the last four years.