You must have SKELETON and GRANITE BLOCK to make TOMBSTONE. This item belongs to signs category. Ever watched the grass grow (IN REAL LIFE)? It is faster than getting this tree ready for harvest. Breaking this block will give you 20 experience points. How many times you need to hit it? Head to the wiki for more info: tombstone Seed mathematics is very complicated, but you should get at least 1 seed back from splicing TOMBSTONE. Gemratio of TOMBSTONE is a mystery. Maybe you can check the wiki for tombstone Massproducing TOMBSTONE can be tricky. You will find out after you have harvested a few.