SIPTU is calling on management at Element Six to engage with workers to avert industrial action.
It comes as a strike is set to go ahead at the Shannon company this month.
Last month, staff at the diamond manufactures voted 96% in favour of industrial action.
Clare FM understands that this action will go ahead on the 21st of September, unless an agrement is struck between workers and the company between now and then.
However, a source within SIPTU insists they wish to avoid a strike if possible and remain willing to engage with the company.
Element Six, formerly known as De Beers, opened in Shannon over fifty years ago.
It currently employs around 400 people, though not all are represented by SIPTU.
Earlier this year, issues relating to a change in working practices at the firm were the subject of a Labour Court case and it was recommended then that workers affected by changes be offered redundancy or redeployment.
