Black sand recommendations

[carriw]

I've been googling sources of black sand since my recent post about sending hubby to pets at home for some and I'm not happy with it as it looks more like fine gravel. Can anyone recommend a good fine soft black sand available to buy in the UK? There is a horror story about tahitian moon sand on here and the unipac limpopo looks to be a similar grain to the PAH one so that's no good either.
Thanks in advance.