Question I want to find out a plugins

Before playing in a skyblock server
i find out one special plugin
when water and lava are meeting together
they not only genera the cobblestone
it may genera the iron , oral , emerlad , lapis , gold ore
who know that plugins ?
and how to set for only one world happen that condition ?
who can help? please

 

thank you i get it

But i find out a problem for the plugin can help me
the chances of ore Default like that
Chances:
Coal: 15
Iron: 25
Gold: 32
Redstone: 38
Lapis: 43
Emerald: 47
Diamond: 50
when all numbers added that will be 250 ( why not 100 )
is not system will count back to 100% like
and what is the chances of the original cobblestone where it is ?
can i enter for like 15% 10% else ?
why the default is using real number , i dont realise that ?
anyone can explain ? and help -,-

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

Coal gets generated 15% of the time, iron gets generated 25-15=10% of the time, etc
Subtract the one before the current one from the current one to get the chance.

Also, I found, not find out.

 

omg do you mean that is a cumulative number ?
and where is cobblestone % ?

 

The cobblestone is natural, if it's under 50, it will change it to something else, if it isn't then it doesn't change the event, thus it generates cobble.

 

the remaining space is for cobblestone ?

 

Yes