There are really a lot of items in the game that give off blue light and bright blue light, here's a list of most of the items. Every now and then I will add new items if they are missing or are added new one to the game.
Store Items
Torch of Change 6sqm
Light of Change 6sqm
Anglerfish Lamp 5sqm light blue
Vengothic Lamp It gives a soft glow
Luminescent Fungi 5sqm
ITEMS
Adamant Shield 4 sqm
Doll of Durin The Almighty 4 sqm
Frozen Heart 3 sqm
Majestic Shield 5 sqm
Mathmaster Shield (also replika) 4 sqm
Blue Sphere 5 sqm
Assassin Doll 3 sqm light blue
Noble Sword (also replika) 3 sqm
Music Box 2 sqm
Old Radio 4 sqm
Frozen Starlight 6 sqm
Eye of the storm 5 sqm light blue
Giant Saphire 6 sqm
Snowbash Figurine 3 sqm light blue
True Heart of the Sea 5 sqm
Shimmer Glower 5 sqm light blue
Soulforged Lantern 2 sqm
Lit Crystal Lamp 4 sqm
Silver Fafnar Trophy light blue 5sqm
Ghostsilver Lantern light blue 4 sqm
Wand of Defiance light blue 3sqm
Starlight Vial 5sqm light blue
Stone of Wisdom light blue 4sqm
Snow Globe 5 sqm
Obsidian Zaoan Bishop 5 sqm
Obsidian Zaoan King 5 sqm
Obsidian Zaoan Knight 5 sqm
Obsidian Zaoan Pawn 5 sqm
Obsidian Zaoan Queen 6 sqm
Obsidian Zaoan Rook 5 sqm
Bunch of Winterberries 4 sqm
Blue Crystal 5 sqm
Surce : tibiafandom, tibiopedia