Maybe I'm totally off here, but are you 100 percent sure that's not an Adromischus rather than a Jade? If my suspicion's right, that's the plant's speckled pattern. Definitely doesn't look like a disease to me; it looks like the plant, and it doesn't strike me as a Jade.

This post was edited by teatree on Fri, Dec 7, 12 at 0:16

Variegated jades are striped so I would bet my money on a adromischus rupicola. But I think jackieg2 is talking about the brown spots in the middle of the picture. I have seen that on some of my jades and don't necessarily associate that with diseases. Could it be sun burn? Any more pictures of where these spots go through the leaf?

Ooooh, Robin, you're right. I'm sorry. Totally missed those spots.

(woops. Why did this submit twice.)

This post was edited by teatree on Fri, Dec 7, 12 at 2:52

It has been suggested that it may be Oedema.
Below what I found on web:

Oedema
Oedema is a condition that occurs when plants receive too much water. Because the plant cells cannot use all of the water, they tend to expand, forming unsightly brown bumps on the leaves of the jade plant. In extreme cases, if left untreated, the brown spots associated with oedema can even spread to the blossoms. Oedema is a more common occurence during the winter months.

Treating Oedema

Several strategies can be employed to reduce the effects of oedema. Succulents should not be watered too frequently, and the soil should be allowed to thoroughly dry out before watering the plant again. Planting the jade in a pot that drains well will lessen the likelihood that the plant will suffer from oedema, and so will making sure that the plant has enough sun to aid in drying out the soil. Remember, it is never a bad idea to remove leaves that are obviously dying; this ensures that the plant does not needlessly divert nutrients in an effort to save dying leaves.

From another site:

Water Salts
If you live in an area that naturally has salts or minerals in the tap water, these salts and minerals can cause your jade plant to develop brown spots on its leaves. The water gets taken up by the root system to the leaves and then the leaves give off the water through transpiration. The leaves can only release water, not the salts. When the salts get left behind, they can burn the leaves. The problem will show on most of the leaves on their upper surface and at the tips. To prevent this problem, give your jade plant filtered water. This type of leaf burn can also happen if you give your jade plant too much fertilizer. Only feed your plant once every three months and follow all package directions so you don't give it too much.

This post was edited by rina_ on Fri, Dec 7, 12 at 7:36

I have got new jade plant, it arrived to my home 2 weeks ago! It develop this black edges , ok 8 leaves are affected! It have got good soil with sand and I placed on sunny window ! We have got now cold winter in uk

Thank you all for your responses. I am new to the forum and am so happy to have fellow succulent/cacti lovers to talk to.

Adromischus it is indeed. I had just assumed it was in the jade family. Here is another photo that shows the spot that goes almost through the leaf. Again, thank you for any suggestions you may have.