Isn't S. dawei a flat-leaved species? Your plant has very round leaves...

Nice plant btw!

Cheers,

Marlon Machado.

this is from a leaf cutting
the juvenile starts usually begin this way

S. dawei has flat leaves, that grow at least a yard tall, that abaxial side has a strong keel, and the adaxial side has a deep wide channal. Very smooth but not waxy or shiny. The some very lighter green variegation on the back of the leaves. My plant leaves grow in pairs, sometimes triples. These leave has a narrow channal half way up,
and quickly broadens to 5-6" wide. My plnt is an adult plant and I had one variegated offset from this plant. Norma Lewis

I forgot to say I don't know why it varietated, the mother plant is a giant dark green plant, I did nothing to cause this. It is a plant that came from Juan Chahinian in 1996, so far no new variegates coming out of the bottom of the pot.