Good or bad may will depend upon why and with what type of wax (and there
are many). Many stone have a high absorbancy and, as a result, we have
trouble removing grafitti that penetrates deep into the surfaces. These
materials can be treated with a wax coating that is essentially invisible
and that can be removed with a low pressure, hot water cleaner. The most
common waxes used are polyethelene waxes and have a high permeability
rating - they allow water vapour to excape the stone without causing
exfoliation or blistering the wax. We have used materials with a
permeability rating of 45.40-g/m2/24 hours based on ASTM E 96, Water Vapor
Transmission testing.

No indications of discolouring or increases in soiling but the latter would
be difficult to evaluate in an urban atmosphere.

Ken Johnson
Victoria

----- Original Message -----
From: "Met History" <[log in to unmask]>
To: <[log in to unmask]>
Sent: 14 June, 2001 8:30 AM
Subject: waxing limestone


> In 1904 the director of the Metropolitan Museum of Art complained about
"the
> disintegrating of the stone of the exterior walls" of the new Fifth Avenue
> wing of the Metropolitan Museum of Art (now the main entrance); "Anyone
can
> see what condition the exterior is in, however, and the necessity of
action
> of some kind", he said.
>
> He said that he supported the plan of "Professor Doremus" [probably Robert
> Ogden Doremus, an analytical chemist teaching at CCNY]  "to coat the
> limestone with wax to preserve the stone", a technique frequently
mentioned
> in the period.
>
> >From modern eyes, were wax coatings beneficial, injurious or of no
effect?
>
> Christopher Gray
>
>