BeginnerEnchanting & brewing
Potion brewing in Minecraft: every recipe in one place
Glowstone Dust raises the effect to level II but shortens it.
Tested 26.3

Glowstone Dust is the glowing powder that glowstone breaks into.
Four dust make a Glowstone block. In a brewing stand, it raises the strength of a potion while shortening its duration, and it turns firework stars into twinkling ones. Witches sometimes drop it, and clerics sell it.
This item has no crafting recipe.
Glowstone Dust raises the effect to level II but shortens it.
It is dropped by Witch.
It strengthens potions and crafts glowstone. It is an ingredient in 2 recipes, made at the Crafting Table; for example Glowstone and Spectral Arrow. Brewing: it turns potions into Potion of Harming, Potion of Healing, Potion of Leaping, Potion of Poison and 6 more.