The Seiji (Green) Nuka is Roger's synthetic with 5% copper

carb added. It is in his book.

Roger's Synthetic Nuka

Potspar 35.6
Whiting 21.8
Talc 2
Bone Ash 2
Ball Clay 5.9
Flint 29.7
ferro3134 3.0 (I have subbed wood ash)

add 4% to 5%copper for Sage (Seiji) in Oxidation (white without) Ox or Reduc

I use Nuka white over this tenmoku:

Temmoku cone 9-10

Whiting 17
Custer 33
EPK 10
Flint 40

R.Iron Ox 11

This was the shino I used in Minnesota:

Linda's Shino
Neph Sy 48
Spod 25
EPK 5
Ball Clay 8
SodaSpar 7
Soda ash 4%

Another you might enjoy:

Reeves Synthetic Mashiko Kaki

OM4 11.5
EPK 11.3
KonaF4 31.4
BoneAsh .5
Talc 5.2
Wollastonite 6.5
Silica 27.0
Spanish Irn Ox 6.4
TiO2 .5
MnO2 .2

LG Clear (I use this under Kaki with was resist:
Porcelain and Stoneware

Custer 27
OM4 14
Whiting 20.5
Flint 31.5
EPK 7

Please share any tests!