A rock, when it gets employed in a dry laid wall, becomes a 'stone'. It now has a job. An employed stone can be any colour, shape, type of material or religious persuasion, and more importantly it can be any...any age.
The newer aged stones, ( usually taken from a freshly quarried source) we like to call toddlers.
Yes, it may seem wrong to put young toddler rocks to work, but then they really are already, millions of years old! The geological material they have broken off from has had plenty of time to form . It's just that having been recently extracted from the bedrock, they've not had a lot of exposure to the elements yet, so their 'character' has not really had time to develop.
In a wall they may look too new, too uninteresting, or worse, too brash or too sure of themselves. Their sharp, freshly hewn faces don't possess that patient beauty and calm humility that only comes with time.
After a while, at a certain age, newly quarried material changes from young 'ado-lesstones' through puberty to full grown adults. They begin to have character.
As they pass from the awkward ages, they maybe start to grow lichen or moss and develop interesting textures. In a wall they will all start to have what is called a 'patina'.
It will take time, but the pre'Patin-Agers' will eventually become as experienced, and look as aesthetically attractive as their wizened elders.
