The Pembrokeshire slime industry

The blue "slime" beneath the peat layer at Amroth.

I was reading a book by Roscoe Howells the other day, and came across a record of the blue "slime" which underlies the raised beach at Amroth, Marros and many other places.  It was a very desirable commodity, and goodness knows how much of the submerged forest was destroyed in the bad old days as people hacked it away at low tide to get at the sticky blue clay.  It was carted away and used for mixing with coal dust in the making of "culm balls" which were used by the poorer members of society to keep their fires going 24/7 throughout the year.  Coal dust was cheap, and blue slime was free.............. and we can assume that this practice was most common in the coalfield areas around Saundersfoot, Wisemans Bridge, Amroth, Broad Haven and Little Haven.

The nature of the deposit makes it difficult to interpret, but it does appear to be associated with outcrops of sticky blue-grey Irish Sea till, which is in turn made mostly of offshore fine-grained sediments.