Biocide for limestone

Leesa Vere-Stevens <leesavere [at] yahoo__co__uk> writes

>Could anyone advise on the most appropriate biocide for the
>treatment of a number of archaeological architectural stone
>fragments which are on display in an outdoor environment and are
>suffering badly from green algae.
>
>The stone fragments have been previously cleaned with water, gap
>filled with lime mortar and consolidated with a protective shelter
>coat composed of lime putty/water/skimmed milk. They are touched
>regularly as they are on display within a sensory garden designed
>for visually impaired people.

I can confirm that Microtech Biocide 25X would be suitable. The
stone fragments had apparently been cleaned with water, gap filled
with lime mortar and consolidated with a protective shelter coat of
lime putty/water/skimmed milk.

Microtech Biocide 25X is a unique fungicidal formulation containing
'Polyphase' for the control of dry rot in walls and the removal and
prevention of moulds, algae, mosses and lichens from both interior
and exterior surfaces.

Microtech Biocide 25X has excellent absorption rates in walls when
spraying or injection. 25X refers to the dilution rate, one litre to
24 litres of clean water makes a final 25 litres of solution.

Because some people with sensitive skins have reacted to the coating
shortly after application the manufacturers recommend any treated
areas are cordoned off and allowed to dry for at least 48 hours,
thereafter however any treated areas will be completely safe to
touch.

We retain stock in the UK and will be happy to provide full
technical details and Material Safety Data sheets on request.

Mark Vine
Conservation Resources
Cowley,Oxford,England
+44 1865 747755


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                  Conservation DistList Instance 16:38
                Distributed: Thursday, December 5, 2002
                       Message Id: cdl-16-38-011
                                  ***