Thanks everybody for the kind words.
Lately I didn't smoke my new pipes cause after a long work I'm scared to damage them! The older ones are good smokers anyway and I always start my work carefully drilling the briar to get a correct air flow and to prevent humidity while smoking.
I obtained the contrasting stain ebonizing the wood with iron oxide, then I sanded the briar till I got the desired contrast between the black and the natural briar color.
The second one is just sanded and varnished.