Tool

Varies

Polishing

Most gems found in treasure hoards and in chests throughout the world are already polished and cut to have a specific shape and feel. Though there are still raw and uncut gems that can be polished and worked to enhance their beauty, increasing how much you can sell them for. When you find uncut or unpolished gems, you can spend 8 hours per gem working and polishing the gem, increasing how much you can sell it for by 5% times your Proficiency Bonus. Once you work and polish a gem, you can no longer work on it again as it has taken its final shape. (This means that if a gem was worth 100 gp when you found it, and it is unrefined, you can spend 8 hours on it and increase its value to 110 gp if you have a +2 Proficiency Bonus (10%) or increase the value to 130 gp if you have a +6 Proficiency Bonus (30%).) This type of activity requires no check.  

Enchanting

Every gem has a special quality within its facets that can be charged and used as protection, divination, healing, and more. Gems found in the world are typically inert, their magic drained out of them, and need to be recharged. Once a gem is recharged, it can be used for only a few hours until it must be recharged again for the next day.   The power of a gem's magic is based on the size of the gem, as larger stones have more magic than smaller gems. This is typically based on the price of a gem as larger gems are more expensive. There are certain, rare cases where a small gem could be more valuable than a larger version of it, per the GM's discretion.  

Recharging

Before a gem can be used, it must first be recharged. This can happen only once per day and requires the gem to gain power. A gem can gain power through a huge variety of ways; a few options include being placed near a fire, on a sleeping cat, under the moonlight, or anything else that produces energy that can be transformed into magic. It must remain in this state for 8 hours while it slowly recharges, changing the energy into magic. A gem can only recharge once per day and so most practitioners sleep during this time. To properly set up gems, a creature must be proficient in Gemologist's Supplies.  

Power

Once a gem has been recharged, they hold this charge until the gemologist activates the gem by using an action. A gem's power is then under effect and any creature carrying the gem on their person gains the gem's benefits. Once a gem is activated, it can not be deactivated until its power is drained and must be recharged.   A gemologist can only activate a number of charged gems equal to their Wisdom modifier per day, regaining all spent uses upon finishing a long rest. A gem only holds its power for a number of hours equal to the gemologist's Proficiency Bonus. Anyone who is carrying the gem can gain the benefits of a gem, but only someone proficient in Gemologist's Supplies can activate a gem's power.  

Size

A gem has three main sizes based on their price of 100 gp, 250 gp, and 500 gp. There are more expensive gems out there, like those worth 1,000 gp and 5,000 gp, but little is known of their power due to their rarity and difficulty of carrying. A larger, and thus more expensive gem, holds more magic within its facets and provides a stronger effect - increasing the potency of the gem. A gemstone's size has no effect as to how long a gem's power is active but does affect the potency of the gemstone's power. Gems that are 10 gp and 50 gp still hold power in them, though that power is very minute and thus doesn't hold enough magic to adequately provide noticeable benefits.  

Types of Gemstones

Each gemstone exists within a family of focus, these families include Dreams, Thoughts, Protection, Transformation, Physical, and many other families. Within these families are different gems that provide different effects, a gemologist might choose to specialize in a specific family in the hopes of unlocking greater secrets, though many will have at least one from each family to act as a safeguard. A gemstone's family has no effect outside of what powers they might have.  

Understanding a Gemstone

The following information is to help you understand the statistics of a gemstone.

  The Gemstone

• A description of the gemstone.

• Family What family the gemstone exists in; Rarity How rare a gemstone is

• Requirements Any special properties or situations that a gemstone must be working under for the wielder to gain any benefits from the gem.

• 100 gp The effect that a 100 gp gemstone of this type would have if charged and activated.

• 250 gp The effect that a 250 gp gemstone of this type would have if charged and activated.

• 500 gp The effect that a 500 gp gemstone of this type would have if charged and activated.

• Special Any unique features or special information about this gemstone, typically if this is included it has to do with the larger gemstones that may have greater properties.

While largely used for decoration and design, gems are precious or semiprecious minerals that are cut and polished. They are often valued for the beauty and wonder they invoke, but some have found ways of unlocking the primal magic of nature within their facets.
Gemologist's supplies include a hammer, set of chisels, a small magnifying glass, and a variety of coarse minerals for polishing.
(See GM Binder https://www.gmbinder.com/share/-MmoewBxvhokK8FVGv1G)

Cost: 100gp
Weight: 10lbs