Bronze disease?

Hello everyone I have just purchased a coin lot and this particular coin is worrying me a bit, is this bronze disease? Any help would be appreciated thank you!

Yep, it is, but it does not look that bad. 

It may be a good idea to clean the coin with unsaturated 100 % alcohol and brush; then dry and cover it with paraloid. Paraloid will cut the oxidizing progress as it will cut of oxygen reaching the corrosion and continue. It will also stop humidity reaching the surface. It will give the coin another century I hope.

And keep it in a acid-free envelope, folder, whatever you keep your coins, especially such early ones with weak alloys in has to be acid-free. 

Thank you so much for your reply and helpful advice, much appreciated!

Paraloid B76 is a easy substance to acquire from chemical firms; but of course you can buy the fancy stuff coin firms sell with fancy names and higher prices:) 

Pure alcohol, no whisky:) And don't drink it, drink the whisky only:):)

Not planning on drinking it lol, thank you for mentioning this method of treatment never knew about it before always heard them mention sodium sesquicarbonate but I have never been able to acquire it locally, this will surely work. Thank you very much 

That is for silver, but one should also be very careful with that. 

Pure alcohol is sold at pharmacies in my country. But it should not be drank or smelled. Ethanol or methanol, one is poisonous. Always wear a mask.  

With copper alloys, it is best to do very light cleaning and cut access to the atmosphere. 

Paraloid is of course easy to remove (again with alcohol); it is a simple wax/resin in fact and can be used on silver and bronze. It does not clean, just cuts access to oxygen and humidity. Basic museum knowledge this one. You can find plenty of literature on it on the net. Renaissance wax will do the same thing if you can access that.  

Spot on advice you are right with copper you always need to be more gentle, renaissance wax is only available online and is very pricey with postage costs as well, paraloid is way better for me. Thank you once again