The Horns and The Snake Duoshade Drawing

Duoshade paper/technique 
Duoshade is an old shading technique used by the comic creators of an earlier time. This method uses a special kind of paper accompanied by 2 chemicals that react with the paper allowing different tones to show through. A dark an a light tone (you can see these tones at the top)
This is one of my favorite mediums. Sadly it was discontinued back in 2009 (a year after I bought mine) 
It is now almost impossible to find. In fact I have been searching everywhere for a place to purchase more for quite some time and I have not been able to find it. 
Luckily I had 3 pieces of paper left from my duoshading kit and a little bit of the chemicals left. It is like gold to me. I don't think there is anything I can do to do it justice because it is so rare. 
I know that you can achieve this same technique in digital art programs like Photoshop, but there is something amazingly enjoyable about seeing it appear like magic before your eyes.