On a whistlestop visit to Tata Steel the Prince commemorated the rebuilding of blast furnace number four - a major £185 million project.
He was then shown a video about the lightweight super-strength steel which could transform safety for British soldiers.
As Charles was taken around the marquee, children from Eastern Primary School performed a series of festive songs.
More top news
Former Cardiff Blues captain Andries Pretorius has been forced to retire from the sport after being diagnosed with a muscle disorder.
As the Met Office issues a cold weather warning, spare a thought for the chimps struggling to keep warm at this Ape and Monkey Sanctuary.
Care workers in the Rhondda who were made redundant say they could lose their homes as redundancy money has still not been paid.