Hi
Nice thread.
stipick_S - Nice tips on the Silverpoint, will try that out. 
Cretacolor Nero - want to share my experience with it here.
What is that ? Cretacolor Nero Stick is a different charcoal pencil, produces the darkest blacks possible, waterproof and doesn’t blurs easily while drawing.
How is that possible? It is compressed charcoal with natural oils (as it reads on Cretacolor website) and some waxes (as I read somewhere else from Cretacolor), this makes this pencil ´unique´.
It has 5 different grades, the number 1 is the darkest and extra-soft.
First time I saw it was with Alex Oliver (Oliveira), he was drawing a KingKong over a Winsor 300g paper, that was so impressive, not only the drawing quality that is obvious to come out from his artworks, but for the image was ´popping out´ from the paper, so strongly, it couldn’t be graphite, there was no reflection at all, looked like charcoal, but was not, and he could draw from light to deep shadows with it.
Now I use it with some studies and generally to get deep darks without reflection, works better than charcoal.
Hope it is useful.
Cheers,