Item Effect
The Primal Glintstone Blade is a Talisman Introduced in Elden Ring.
An old glintstone blade that has been stained with blood. Reduces FP consumption of sorceries and incantations at the cost of maximum HP.
The old sorcerers would slice open their hearts with these blades to imbue a primal glintstone with their soul, and thus did they die.
Primal Glintstone Blade Effects
This Talisman decreases the FP consumption of all your Spells, Sorceries and Incantations by 25%. At the same time, this talisman decreases your Maximum HP by 15%.
How To Get The Primal Glintstone Blade
This Talisman can be found in the Mountaintops of the Giants, in the Stargazers' Ruins. You'll need the 
Spirit Jellyfish Ashesto get this Talisman.
Reach the Ancient Snow Valley Ruins Site of Grace, and from there, head northeast until you reach the frozen river. After that, head west, following the river path, until you go around the plateau to your left. You'll eventually find a Spiritspring to go up; use it.
Once at the top, head to the ruins nearby and explore them until you find a Jellyfish with some dialogues, looking for her sister. Here's when you must use your Spirit Jellyfish Ashes to invoke a jellyfish that will interact with the one in the ruins.
You'll get a message saying that a seal has broken somewhere, and you'll also get the 
Fancy Spin Gesture. The broken seal is inside the room next to where the Jellyfish was. Enter the room, open the door, and then open the chest inside to get the Primal Glintstone Blade.
Extra Primal Glintstone Blade Notes
- You can sell this item for 2000 Runes.