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Cut gems.

Gems can be obtained from mining and trading with other players. Using the Crafting skill, uncut gems can be cut, combined with precious metals to make jewellery and then enchanted using the Magic skill. Gems can also be cut into gem bolt tips. Wearing a charged Amulet of Glory increases a player's chances of unearthing a gem whilst mining. However, one does not receive any additional Mining experience if one manages to mine a gem in such a fashion.

Gems also are a frequent drop from a wide range of monsters and are occasionally given out as gifts from various random events. Random events and monster drops generally give sapphire, emerald, ruby or a diamond. Dragonstones are dropped only by some of the higher level monsters, although any monster that drops gems and many random events, can drop or give Half of a keys to unlock a chest in Taverley, the contents of which include uncut dragonstone.

The statutes in Bandos's throne room frequently drop cut gems from sapphire through diamond, making the room popular for some gem hunters who can kill the statutes easily. The quest The Chosen Commander is required for access to the throne room.

Gems can also be mined from the gem rocks in the north-west corner of Shilo Village, Lunar Isle Mine and occasionally in Tai Bwo Wannai Cleanup minigame. Gem rocks contain, in order of highest probability, opal, jade, red topaz, sapphire, emerald, ruby and diamond.

Some gems can be purchased, stolen or sold to a gem shop identified with a red gem icon on the map.

The original free version gems were officially released in the crafting update in May 2001. In March 2001, Jagex made gems appear while mining, although it was unintentional.

Ironically, uncut gems are worth more on the player market than cut gems are as players are able to get more Crafting experience from cutting gems.

Because of the high price of uncut gems, it is recommended that players keep the gems they find if they are mining lower levelled ores such as coal, but drop them if they are mining ores such as adamantite ore or runite ore.

From TibiaWiki

Valuables are items that have no "practical" use, but are generally worth a lot of money. Most gems and jewels are very valuable, and many of them can even be sold to NPCs for lots of gold.

The following items are considered "valuable".

Valuables

Name		Attributes	Weight	Dropped By
Black Pearl		stackable	0.20	Vampire, Mummy, Banshee, Lich, Quara Pincher, Vashresamun, Orshabaal, Morguthis, Quara Hydromancer, Hellhound, Ice Golem, Thul, Zugurosh, Mutated Bat, Golgordan, The Plasmother, Zevelon Duskbringer, Latrivan, Ushuriel.
Blue Gem		None.	0.30	Marid, Defiler, Dipthrah, Orshabaal, Zugurosh, Annihilon, Fahim The Wise.
Christmas Token		stackable	0.05	None.
Countess Sorrow's Frozen Tear		None.	10.00	Countess Sorrow.
Crown		Unknown	19.00	None.
Crystal Coin		stackable	0.10	Ghazbaran, Grynch Clan Goblin.
Crystal Wand		None.	28.00	Rahemos
Crystal of Balance		None.	8.50	Nightstalker.
Crystal of Focus			8.00	Nightmare Scion.
Crystal of Power		None.	8.50	Infernalist, War Golem.
Emerald Bangle		None.	1.70	Vampire, Wyvern, Hellfire Fighter, Hand of Cursed Fate, Plaguesmith, Vampire Bride and Zulazza the Corruptor
Giant Shimmering Pearl		stackable	0.80	Killer Caiman, Water Elemental, Roaring Water Elemental, Annihilon
Gold Coin		stackable	0.10	Almost every creature.
Gold Ingot		stackable	18.00	Dark Torturer, Ferumbras, Ghazbaran, Hellhound, Infernalist, Juggernaut, Lord of the Elements, Undead Dragon, Yakchal, Zugurosh, Orshabaal, Blightwalker, Ushuriel, Golgordan, The Many, Chizzoron the Distorter.
Gold Nugget		stackable	?	None.
Green Gem		None.	0.30	Efreet, Defiler, Orshabaal, Thalas, Ushuriel, Zugurosh, Annihilon, Ghazbaran.
Holy Scarab		None	8.70	Ashmunrah
Orichalcum Pearl		stackable	0.30	Grynch Clan Goblin, Betrayed Wraith, Hellfire Fighter, Massacre, Grim Reaper, Dark Torturer
Platinum Coin		stackable	0.10	Orshabaal, Defiler, Juggernaut, Destroyer, Blightwalker, Hand of Cursed Fate, Undead Dragon, Spectre, Bones, Nightmare, Demon, Lost Soul, Betrayed Wraith, Hellhound, Grim Reaper, Diabolic Imp, The Imperor, The Plasmother, Vampire Bride, The Noxious Spawn, Water Elemental.
Red Gem		None.	0.30	Stone Golem, Mahrdis, Grorlam, Fury, Annihilon, Zulazza The Corruptor.
Rusty Armor (Common)			120.00	Mutated Human, Damaged Worker Golem, Mutated Bat, Zombie, Earth Elemental, Crazed Beggar, Young Sea Serpent.
Rusty Armor (Rare)			120.00	Blightwalker, Medusa, Grim Reaper, Zugurosh, Lost Soul, Plaguesmith, Juggernaut, Hellgorak, Undead Dragon, Zulazza the Corruptor.
Rusty Armor (Semi-Rare)			120.00	Worker Golem, Massive Earth Elemental, War Golem, Hellspawn, Vampire Bride, Massive Energy Elemental, Werewolf, Water Elemental, Ghastly Dragon, Leviathan.
Rusty Legs (Common)			70.00	Crate (Usable)
Rusty Legs (Rare)			70.00	Fury, Hellgorak, Zugurosh, Leviathan.
Rusty Legs (Semi-Rare)			70.00	Worker Golem, Water Elemental, Leviathan.
Scarab Coin		stackable	0.20	Scarab, Ancient Scarab, Grynch Clan Goblin.
Silver Brooch		None.	1.10	Ashmunrah, Banshee, Mummy, Spectre, Plaguesmith.
Small Amethyst		stackable Enchantable	0.10	Ancient Scarab, Behemoth, Destroyer, Diabolic Imp, Dwarf Guard, Energy Elemental, Ferumbras, Fire Devil, Grorlam, Lizard Snakecharmer, Merlkin, Minishabaal, Mutated Bat, Quara Constrictor, Quara Constrictor Scout, Scarab, Rahemos, Thul, Ushuriel.
Small Diamond		stackable	0.10	Assassin, Crypt Shambler, Deadeye Devious, Dragon, Ferumbras, Ice Golem, Lizard Sentinel, Novice of the Cult, Omruc, Orshabaal, Quara Predator, Quara Predator Scout, Valkyrie, Betrayed Wraith, Hellfire Fighter, Tiquandas Revenge, Morgaroth, Wyrm, Defiler, Madareth, Worker Golem, Golgordan, Ushuriel.
Small Emerald		stackable /Enchantable	0.10	Acolyte of the Cult, Ancient Scarab, Bog Raider, Demon, Efreet, Elder Beholder, Ghazbaran, Golgordan, Green Djinn, Haunted Treeling, Lizard Templar, Medusa, Morgaroth, Orshabaal, Phantasm, Scarab, Thalas, Ushuriel, Water Elemental, Killer Caiman.
Small Enchanted Amethyst		stackable	0.10	Dark Magician, Mad Scientist
Small Enchanted Emerald		stackable	0.10	None.
Small Enchanted Ruby		stackable	0.10	Infernalist
Small Enchanted Sapphire		stackable	0.10	None.
Small Ruby		stackable Enchantable	0.10	Amazon, Valkyrie, Hunter, Mahrdis, Adept of the Cult, Quara Pincher Scout, Quara Pincher, Hellfire Fighter, Defiler.
Small Sapphire		stackable Enchantable	0.10	Dragon Lord, Hydra, Demodras, Blue Djinn, Serpent Spawn, Orshabaal, Marid, Dipthrah, Dwarf Geomancer, Enlightened of the Cult, Ice Golem, Wyvern, Quara Mantassin Scout, Quara Mantassin, Frost Dragon, Warlock, Bones, Sea Serpent, Young Sea Serpent, Ferumbras, Zugurosh, Ghazbaran, Gozzler, Latrivan, Ushuriel.
Small Topaz		stackable	0.10	Hellspawn, Earth Elemental, Massive Earth Elemental, Hellgorak, Ferumbras
Vampire Lord Token		stackable	0.05	Sir Valorcrest, Arachir The Ancient One, Diblis The Fair, Zevelon Duskbringer
Violet Gem		None.	0.30	Rahemos, Hand of Cursed Fate, Annihilon, Zulazza the Corruptor.
White Pearl		stackable	0.20	Blood Crab, Lich, Banshee, Quara Hydromancer, Quara Hydromancer Scout, Vashresamun, Fury, Medusa, Morgaroth, Thul, Dark Torturer, Golgordan, Ushuriel.
Yellow Gem		None.	0.30	Elf Arcanist, Omruc, Lizard Snakecharmer, Lizard Dragon Priest, Dharalion, Annihilon.

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