you learn the power locked within gemstones.their are many before like you many thought that certain gems had medical, psychic or magical powers and held great power.the correlation between the mind and gems is not to be understated, in many cultures they were used in therapy.these ideas come from the thought that if it bent light it can bend magic and energy and that its orderly structure brought order to the world around it.you still use the ancient practices tapping into the magic of gemstones and creating them thin air.

gemstone amulet

Beginning when you select this school at 2nd level,you can spend 30gp and 3 gemstones on a long rest to make a gemstone amulet which you can use as a focus and while you have it you can spend one gem to charge it with the correlated school of magic if you cast a spell of that school while its charged you heal a number of hit points equal to your int mod you can only have 1 gem amulet at a time and it can only be charged 1 school of magic at a time.you gain prof in jewelers tools 

create gemstone

Beginning at 2nd level, you can use the energy of your magic to form gems to help your allies ,when you cast a spell of first level or higher you get a gem of the type that comes with the school of the spell plus 1 more gem per 2 spell levels the spell you cast.as an action you can harness the power of the gem, and choose a creature within 30ft of you the gem loses it power  and the chosen creature gains the effect of the gem you used for one minute.when a gem loses its power it becomes a simple obisidian rock worth 1 gp.you have use this feature a number of times per day up to your int mod and these gems are near worthless themselfs.you can have a maxium of your int mod at a time. 

rose quartz (abjuration):you call upon the calming power of rose quartz to add your int mod to one save the target makes per round

citrine(conjuration):you call upon the  power of citrine to make leaps of faith the target can can teleport 10ft as an bonus action 

diamond(divination) you call upon the mind boosting powers of diamond choose a skill for the target has prof in that skill if they did not have it already if they did they gain advantage on checks with that skill 

blue topaz(enchantment):you call upon the courage giving of blue topaz the target is immune to the frightened condition 

aquamarine(evocation) you call upon the power of aquamarine to bring clarity for your allies to strike when they roll a 1 on a damage die they can replace it with your int mod damage 

iolite(illusion) you call upon the reflective power of iolite the target has a single mirror image when a attack against you would hit it instead misses and you lose the effect of this gem 

black garnet(necromany) you call upon the stimulating power of garnet if the target has advantage on death saves while under the effect of this gemstone

smokey quartz(transmutation): you call upon the enduring power of smokey quartz the target gains a number of temp hit points equal to your int mod 

 

gemstone cleansing

Starting at 6th level, you can use your gemstones to cleanse you can expend 5 gemstones to choose you creature to within 30ft of you they can remake all saves affecting them with advantage and heal a number of health up to your wizard level.you can spend more gemstones adding your wizard level to the healing for every five additional gemstones.

gem casting

Beginning at 10th level,you can spend 2 or more gems of the same type to cast a spell of up to half the gems expended in level and of the school of the gems you expended that you know without expending spell slots or materiel components 

endless gems

Starting at 14th level,you can use create gemstone any number of times per day and have no max number of gemstones from it.