L-deck evaporator bedding material

[Electrocoolman]

Hi guys,
Has anybody experience of 'L-deck evaporator' construction (as found in old butcher shop window displays) ?
A local butcher that I service, has had his display apart (stainless steel cover off) and said "the concrete had gone powdery in places".
I pointed out that I doubted that it was 'concrete or cement' due to copper / chloride reaction.
Has anybody any idea what might have originally been used to bed the pipework in?
Unfortunately, I didnt get to look when he had it apart so I don't know what the complete construction is.

Thanks, Adrian

[lowcool]

more than likely a heat transfer paste thats broken down