The Sapphire is the first and lowest of 5 tiers gem available to use with various items. A player will at least need 9 Sapphires to upgrade tools and do everything you need.
|6 in total
(1 for each)
|1||You need to sell one sapphire to npc to unlock the Gem Goblin Shop|
|1 for each display|
|1 for each key||Gives more items slots|