The Jewel Worm is a real menace to those who work or explore underground. Every summer they lay their eggs in small hollows that they scrape out of the wall. These eggs, depending on the type of worm, look like diamonds, saphires, rubies or emeralds. Often the worm will merely knock a genuine gemstone out of the wall a genuine gemstone and put it’s egg in it’s place. Young worms are only a few inches long and silver coloured and even at this stage their favourite food is stone, but they will eat anything nearby-the leather of an adventurer’s backpack, human flesh, any insect or bat passing by, as well as their egg case. They don’t eat genuine jewels however, as it gives them a very bad stomach.
As quickly as possible they will try and hide in shadows and any cracks in the stone they can find, and will bite their way into the stone in a matter of days, excreting it smallas dust. At this stage they find wooden pit props are also to their taste, and a severe infestation of these worms can make it prone to cave-ins and downright dangerous.A blow from a weapon will kill a juvenile Jewel Worm and many are killed by miners.
They stay at this small size for several years and then they change. They grow much larger and the biggest ever encountered was larger then a crocodile. They also become territorial, killing and eating their own kind except in the case of mating, after which the female will lay a batch of up to twenty eggs at a time. Their diet switches to stone except in self defence of themselves or their eggs.
A fully adult Jewel Worm looks very like a small wingless and legless dragon and it’s skin is very hard indeed, almost stone like, and silver in colour.Ordinary swords will bounce off most of it and can only pierce the eyes and the inside of the mouth, although enough blows with a warhammer,pickaxe or battle axe will pierce it’s hide and kill it.Most never reach this stage,killed by humans, bats or each other.
If they do not die violently they can live for centuries, having a growth spurt at the age of five in which they grow to three feet within months, and then only growing a few milimeters taller each year.The large ones are very old indeed and their jaws have been known to bite limbs off and snap weapons in two.
There have been cases where their eggs were mistaken for jewels and ended up in royal tresuries, with the result that when they hatched out, they ate a large amount of the tresaure around them, plunging whole kingdoms into temporary bankruptcy and bringing major banks crashing down.
Although any jewels that were around them survived, the gold bars and any documents and paper money were eaten.
The Jewel Worm dislikes strong light and stays underground whenever possible, and the adults only fight in self defence and will not pursue far.