There are many Lead White hues out there which are unsurprisingly approximations of the hue of real Lead Carbonate white, but none which try to also approximate the handling qualities.
Most are generally Titanium white with a little earth added to warm them, which frankly anybody could do on the palette, this paint has a lot more going on.
This paint attempts to mimic both the hue and the qualities of Flake White, the picture opposite is of the actual paint.
It has a gentler tinting strength compared with Titanium White, lower chroma (not a blinding white) and a certain stringyness in handling, faster drying, all these are qualities are present in the genuine thing.
This is the best alternative I have used, great value and of course non-toxic.
Pigment - Special grade of Zirconium Oxide
Opacity - Semi-Opaque
Binder - Linseed Oil
Drying Time - Medium/Fast