minecraft observer recipe
The whole cost here is mining: no smelting, no coal. The tool below opens on the observer and works out how much cobblestone, redstone and quartz goes into a batch.
Cobblestone above and below, and in the middle two redstone in a row with the quartz at the right end. The layout is not symmetric.
It is 6 cobblestone, 2 redstone and 1 quartz, and nothing goes through the furnace, so coal is zero.
The 96 cobblestone take 1 stack plus 32. The 32 redstone and the 16 quartz each fit in less than 1 stack.
The block loot table returns the observer itself.
It adds up what each item needs across all branches and only then rounds the number of crafts up. One log makes 4 planks; if you need 5, that is 2 logs and 3 planks left over. Leftovers show on the Materials tab and are reused by other items on your list before more raw material is requested.
It is 6 cobblestone per observer. For 16 it is 96, which is 1 stack plus 32.
Yes, 1 per observer, at the right end of the middle row. The 16 observers in a batch take 16 quartz, less than 1 stack.
Neither. All three ingredients are raw, so furnace items and coal stay at 0, for 1 or for 16.
A pickaxe: the block has the mineable/pickaxe tag and drops itself. That is the fact from the Java 26.1 data.