Enamel(ing) Advice: Blythe's acid resistantance?

Perhaps some of the readers familiar with enameling could share
their wisdom on Johnson Matthey’s Blythe Enamels.

Just how acid and chemical resistant are the older transparent
Blythe enamels?

In particular, # 225 Green (date on package is 9 December 1975) & #
788 Blue (not dated on package …may be mid 1970’s too). My
original 1/2 kilo packages for #'s 225, 788 & 2092 indicate
transparent colors.

In Jeanne Werge-Hartley’s book she provided a very useful table of
technical on firing temperatures (attributed to Vitrum
Signum on pg. 162). However, I have an void when it
comes to chemical and acid resistance of these transparents; and I
am contemplating electroforming some Blythe enameled pieces.

As I recall; the following are probably 25 year old Blythe product.
Possibly someone knows of an old Blythe product profile similar to
that found in “Enameling on Precious Metals” with technical data on
temps and flow point for the following (not found in Jeanne’s book):

OPAQUES 
557     Purple
682     Green
684     Blue
1924    Blue
2174    Blue
3016    Brunswick Green K31
3040    Mauve A25

Transparent 
225     Green       (date on package is 9 December 1975)
242     Chedron
788     Blue        (not dated on package may be mid 1970's)
935     Red
1072    Yellow
2092    Gray Green  (date on package is 5 Aug 1978)

Opalescent  
1533    White

Regards,
Mark

You might be able to get the you need about Blythe’s
acid resistance from Thompson Enamel as they carry the Johnson Mathey
leaded enamels. I use them, but mine are fairly new, mostly
opaques, and I have never had need to subject them to acid.