relief for designer planters

We are currently working on a project for the Fraser Coast Council which sees our planters with a low relief (bas-relief) design on one side of each planter. This is achieved by placing a reverse relief inside the planter mould then casting in glass fibre reinforced concrete (GRC). To ensure the relief design remains crisp and intact, a rubber film is placed over the mould which when almost dry is peeled away to expose the artwork.