Mining Turtle

I was curious if there is a way (or simple program) that makes a Mining Turtle dig specific blocks? For example, if the excavate command was used but the turtle only mined the smooth stone and left everything else. I've seen programs (like Ore Quarry) that mine everything EXCEPT certain blocks but that's not what I want. I'm new to ComputerCraft and have never used the Lua programming language. If there is already a program for this I apologize as I was unable to find it. Google can only do so much with "mining turtle". LOL! Thank you for the help!

Split into new topic.

The only way to do anything like this is to use turtle.compare(), turtle.compareUp(), and turtle.compareDown(). The compare functions uses the block the turtle currently has selected and compares it to the block in front/above/below it. If they are they same, it returns true. So you could do something like this:

local slotsNum = 3 -- number of slots to check
local slotsToCheck = { 14, 15, 16 } -- slots with blocks to check

function shouldMine()
    for x = 1, slotsNum do
	  turtle.select(slotsToCheck[x])
	  if (turtle.compare) then
		 --mining code
	  end
    end
end