It has been used in the past for seed compost. The rubbish the moles bring up here contains so much glass and scrap iron that it is no use.

Do moles go into the sub-soil which you don't want? I don't know. No rubbish where I see them.

The moles only bring to the surface whatever soil you have in your garden, if you have good soil, that is what you get, it only looks good soil because of the small amount at a time that they throw up, if you used a teaspoon and ground it down, that would look like good soil as well, but it would still only be the soil you have in your garden, Derek.

Thanks Derek.

So going on that the mole hills I see are by a beach front from undisturbed natural turf/ grassland. Will the soil have any nutritional advantages?

If the grass is growing in more or less pure sand at the edge of a beach, then I would not expect there to be much in the way of nutrients, there may be a small amount of humous directly under the grass, but hardly enough to be of any benefit to your garden, Derek.

And the soil belongs to the landowner too!

My mother was a keen gardener. She used to send me across the road into the field with a bucket to collect mole soil for the greenhouse. Also when the sheep were in to collect sheep droppings to make liquid manure, by putting it into a tied up sack and dangling it in the water butt. This was when John Innes Composts were first invented.
We had 2 pigs (it was in the war) and she used to pen them in an area with wire netting. They used to dig the ground and chew all the Couch Grass roots, leaving it ready for planting the seed Potatoes.
When the slaughterman had to come, she cried.
I remember when Catriona Potatoes first came out. She never stopped getting excited about them, huge tubers.