A ghastly lack of gerstley: introducing "Carl's Sat. Iron Fuggup"

I ran into the trouble of not having Gerstley Borate when mixing a Saturated Iron and kaki glaze... part brain fart, part naivete, I thought I had ordered Gerstley when in fact I hadn't. I thought g200-hp was gerstly, when in fact it is a potash feldspar. I recognized it when doing the Sat. Iron recipe called for both Gerstley and potash. I found myself adding  the same feldspar as two different ingredients....

I had already made messed up a kaki glaze:

KAKI:

Potash  27           (supposed to be Gerstley)
Silica 25.3
Custer  16.9
RIO  12.8
Talc 11.8
EPK 4.2
Bentonite             2    
                                100

I was in the middle of making the following when recognizing my mistake:

Saturated Iron Glaze  (originally)

Red Iron Oxide 24.6
Gerstley Borate 28.9
Flint 20.2
Potash Feldspar 13.4
Talc 9.4
EPK 3.4    
99.9

  Thick it produces a nonshiny iron red. When Thin it’s a smooth brown, greenish, with hints of blue. Fire to ^6  When over a Kaki Glaze it produces a beautiful copper sheen.  Needs to be thin to get the Tenmoku effect.

In my frustration (because who wants to waste 100g of glaze chemicals) I split the 27 gerstley among the other ingredients as follows:


Sat Iron fuggup:

RIO                  30.6      (+6)
Potash Feld,     28.9      (+15.6)
EPK                 3.4        (+0)
Talc                  9.4        (+0)
silica                 21.6      (+1.4)

I also added :
    Bentonite             2     (+2)
     3134                    6     (+6)


In my amateur rationale, I split it up by my understanding of gerstley.

+6 RIO because I had to put it somewhere and I figured it would act in part as flux characteristic of Gesrtley

+15.6 Potash because I had already measured it out as the gerstley

+1.4  Silica because I thought the RIO's flux quality might do too much

+2  Bentonite because(as I remember) I learned of it's benefit when added to other glazes in helping fit because of its tiny particle size

+6  FF3134 for the borate


I'm not sure of the effectiveness of this, but it seemed to work. I have no idea of its durability or stability and it looks nothing like the copper sheen as advertised by the real recipes with gerstley borate. The modified Saturated Iron looks more like a ketchup glaze as seen on the tile in the back.  the front test is a sample of a sculpture body I tried out. I was able to really gob it on the because of it's gritty texture. the sculpture body has a layer of the kaki with potash in place of gerstley. I may playaround with what we shall call henceforth as "Carl's Sat Iron Fuggup"