Hi Jos, Happy New year!
Sorry, can't add anything to the silk weavers, but I've been doing some similar investigation on brass founders in Islington in the same era - it was the Silkweavers 'tag' that caught my eye.
However on reading your post I was also attracted by your names list. I have a Fenwick brother-in-law who was born in Co Durham, trained as a mining engineer and has spent the last 40 or so years travelling the world as a mine manager (or better) - Rhodesia, Namibia, South Africa, Brazil, etc. and is now retired and resident in South Africa.
We visited him a couple of years ago and he very proudly showed me a map of the Border country that he has framed and hanging on a wall. It flags up Revier families and locations and he was very proud of his reiver background.
He had brother who died recently who had been a school teacher in Spennymoor I think.
I would be interested to hear more of your Fenwick line - what period are you interested in?
Vic