That looks like scale to me. Norma

Looks like scale to me too.

That's what I thought at first, too, but the white splotches are actually scar tissue on the leaf, rather than 'flakes', like scales are.

i have never had this problem. i am not convinced that that is what it is, but, there are more than one type of scale insect, from my research on this post.

and if it is not scale. my next questions would be: what kind of potting soil is it in? how often do you water?

i could be wrong but i know that i read somewhere that a plant that takes up water too fast can produce bumps on its leaves, for whatever that is worth.

Doug

Ron is right. it is scale but different scale (animal) inside:-)
yes it has some scars but other things are some scale patches and inside that is some kind of egg-bug or whatever the name in english is.
I did have that some years back too, some of them i squeezed and when summer came those things were gone.
my jade is about 10 years old in the same soil , same water same owner, but some years those things would show up, particularly when jade is to dense, that's my experience.

Best wishes