Kids book where the main character has metal under his skin

Question

I read a book when I was in school in the UK, probably around year 2000, all I remember is the main character I think is found by a group of kids and they look after him. He gets increasingly unwell and his skin starts falling off, only to discover he is made of metal underneath the skin (possibly gold or copper). I don’t remember if the other kids have superpowers or not. I just have a visceral memory of this boy shedding his skin to reveal a metal.

Answer 1

The Silver Child by Cliff McNish

Six children leave home and are drawn to Coldharbour - an eerie wasteland of wind, rats, gulls and rubbish. Each of them has a unique gift, but they must learn to use their skills fast. Drawing ever closer in a maelstrom of fury is the Roar, something vast and dreadful that wants to destroy them.

From the book:

Milo glanced down. There was a small gash on his left wrist. He must have accidentally cut it while he was on the river bank, though he could not remember doing so. There was no pain from the cut, but there was light spilling out — golden light.

Milo was intrigued rather than frightened. But he was frightened enough of the gang of boys. How could he defend himself? Thrusting his arm forward, he deliberately pulled the skin either side of the cut further apart. More gold splashed out, illuminating the ground. Milo widened the cut, feeling no discomfort.

He had initially left home because his hair suddenly started falling out. After he is covered with golden skin, it sloughs off to reveal silver.