Helllo Raf
The source you quoted from the 1639 Inventory of the Tower of London is very interesting, can you please tell me where it is published?
Fernandos grenade, which comes from the Ingolstadt find is an explosive grenade- These grenades work through the fragments of the vessel parts shattered by the explosive charge they contain. In the more than 500 grenades examined so far, we have found no evidence that the black powder charge was mixed with other objects such as iron splinters, stones, flint pieces or the like.
The ones in the London inventory sound more like fire or lime pots (in German: Sturmtöpfe). Similar to a mordern molotov cocktail.
All this military fireworks is very interesting. Here is a link to our German webpage about such devices:
https://www.bummsbrigade.de/index.ph...feuerwerk.html (unfortunately only a view pages are available in English so far)