Dragon scale vs normal scale
This is what I told my new friend LizzyP just a few days ago:
Apparently, dragon scale refers to a scale mutation. From what I have explored (I'm not an expert, just amateur relying on what I can see), those bettas present a different shape of their scales. Instead of the traditional hexagonal shape, this scales appear to be rhombus shaped [with one side more curved instead of straight] and they present a kind of overlapping pattern of scales that is more pronounced that the pattern on the more normal bettas.
My friend LebronTheBetta also told us that dragon scales present different coloration patterns and are more brilliant in color. You can visit their sites and post as well as mine for more details.
Come to my site anytime.