Editing Polestone

{{culture
|related=[[Spheres]]<br/> [[Soulcasting]]<br/> [[Fabrial]]s
|world=Roshar
|universe=[[Cosmere]]
|books=[[The Stormlight Archive]]
}}
{{update|sa4}}
The '''Polestones''' are the ten varieties of gemstone that naturally hold [[Light]]. They also serve as the basis of [[spheres]], the basic Rosharan money system.{{book ref|sa1|3}}

== Attributes ==
=== Composition ===
Some Polestones are the same type of crystal but with different color and chemical signatures. Sapphire and ruby are both types of corundum. Smokestone and amethyst are both types of quartz. Emerald and heliodor are both types of beryl. Much like how [[iron]] and [[steel]], despite being very similar chemically, are different metals in the [[Metallic Arts]], the exact color and chemical signatures are enough to differentiate the Polestones. As a result, an off-color Polestone acts much like an impure alloy in [[Allomancy]].{{wob ref|4080}} If a Polestone was drained of its color by an [[Awakener]], it would still hold Stormlight but would have the properties of a dusty or cloudy quartz.{{wob ref|3203}}{{wob ref|295}} If a spren was trapped inside, they would be released.{{wob ref|292}}

If sung to, while holding Light, Polestones will break.{{book ref|sa4|86}}

=== Light and Surgebinding ===
All Lights can be stored in gems. How long a given quantity of Light will remain in a specific gem depends on the type of Light and the quality of the gem.{{book ref|sa4|16}} The rate at which a Light leaks from gemstones is not constant either - it appears slow at first, but accelerates rapidly near the end, making gems that begin to dim, dim ''fast.''{{book ref|sa4|32}} Regardless of the type of Light, perfect gems are said to be able to hold it indefinitely, but they are extremely rare.{{book ref|sa4|13}}

Although the type of Polestone Stormlight is stored in is irrelevant for most [[Surgebinding]], Polestones do have an important impact on Soulcasting. Namely, they determine what kind of substances a Soulcaster can transmute objects into.{{wob ref|2784}} It is believed to be impossible to create Polestones via Soulcasting.{{book ref|sa1|33}}

=== Spren ===
In addition to the ability to hold Stormlight, Polestones are able to trap [[spren]]. The type of spren that can be trapped depends on the Polestone used and its cut. This quality serves as the basis for [[fabrial]]s.{{ref|name=Navani1}} Each Polestone is associated with one of the [[Ten Essences]] and with an Order of [[Knights Radiant]].{{book ref|sa1|part=ars}} However, there appears to be no functional difference between Polestones apart from [[Soulcasting]] and fabrial creation.

If a Polestone is set in the pommel of a deceased [[Shardblade]] it allows the blade to be bonded, whereby it can be summoned and dismissed.{{book ref|sa2|67}} Synthetic versions of the Polestones could also be used in fabrials.{{wob ref|2702}}

== The Ten Polestones ==
=== Sapphire ===
'''Sapphire''' is associated with the Essence of Zephyr. They are used to Soulcast translucent gases, like air.{{book ref|sa1|part=ars}}

Sapphire spheres are given the "sky-" prefix.{{book ref|sa1|27}}

It is associated with the [[Order_of_Windrunners|Order of Windrunners]]

=== Smokestone ===
'''Smokestone''' is associated with the Essence of Vapor. They are used to Soulcast opaque gases, like smoke and fog.{{book ref|sa1|part=ars}} 

Smokestones are used in a type of fabrial clock.{{book ref|sa1|10}}

It is associated with the [[Order_of_Skybreakers|Order of Skybreakers]].

Smokestone is a chemically impure version of quartz.{{wob ref|3813}}{{ref|group=fn|text=It can be reasonably assumed that smokestone is [[wikipedia:Smoky quartz|Smoky quartz]], a form of quartz turned a dark grey due to aluminum impurities within the crystalline quartz. This is confirmed due to the fact that Brandon confirms that smokestone is an impure form of quartz.{{wob ref|3813}}}}

=== Ruby ===
'''Ruby''' is associated with the Essence of Spark. They are used to Soulcast fire.{{book ref|sa1|part=ars}}

Rubies are used in the production of [[Fabrial#Pairing fabrials|conjoiner fabrials]], where a single infused ruby is split in two. Once activated the two halves will mirror each others movements, lift one and the other will also rise.{{book ref|sa1|part=ars}} [[Spanreed]]s are a common application of this phenomenon.{{book ref|sa1|28}}

Rubies are also used in a kind of heat producing fabrial.{{book ref|sa1|15}} They are also used in the construction of a [[painrial]], a pain reducing fabrial, designed by [[Longshadow]] and adapted by [[Navani Kholin]].{{book ref|sa1|22}} A ruby was also part of the [[Oathgate]] at the center of the [[Shattered Plains]].{{book ref|sa2|86}}

Ruby spheres are given the "fire-" prefix.{{book ref|sa1|3}}

It is associated with the [[Order_of_Dustbringers|Order of Dustbringers]]

=== Diamond ===
'''Diamond''' is associated with the Essence of Lucentia. They are used to Soulcast crystals, like quartz and glass.{{book ref|sa1|part=ars}}

Diamonds are used in a kind of light producing fabrial.{{book ref|sa2|86}}

Diamond spheres are given the "clear-" prefix.{{book ref|sa1|11}}

It is associated with the [[Order_of_Edgedancers|Order of Edgedancers]]

=== Emerald ===
'''Emerald''' is associated with the Essence of Pulp. They are used to Soulcast plant material, like wood, moss, and grain.{{book ref|sa1|part=ars}}

Emeralds can be used to capture flamespren.{{ref|name=Navani1}} They can be found in [[chasmfiend]]s.

It is associated with the [[Order_of_Truthwatchers|Order of Truthwatchers]]

=== Garnet ===
'''Garnet''' is associated with the Essence of Blood. They are used to Soulcast the eight types of blood and all other non-oil liquids.{{book ref|sa1|part=ars}}

Garnets are used in a type of water attracting fabrial.{{book ref|sa2|82}}

Garnet spheres are given the "blood-" prefix.{{book ref|sa1|17}}

It is associated with the [[Order_of_Lightweavers|Order of Lightweavers]]

=== Zircon ===
'''Zircon''' is associated with the Essence of Tallow. They are used to Soulcast oils.{{book ref|sa1|part=ars}}

It is associated with the [[Order_of_Elsecallers|Order of Elsecallers]]

=== Amethyst ===
'''Amethyst''' is associated with the Essence of Foil. They are used to Soulcast metals.{{book ref|sa1|part=ars}}

Amethysts are used in the production of [[Fabrial#Pairing fabrials|reverser fabrials]], where a single infused amethyst is split in two. Once activated the two halves will inversely mirror each other's movements, lift one and the other will be lowered.{{book ref|sa1|part=ars}}

It is associated with the [[Order_of_Willshapers|Order of Willshapers]]

=== Topaz ===
'''Topaz''' is associated with the Essence of Talus. They are used to Soulcast rock and stone.{{book ref|sa1|part=ars}}

A topaz was observed as part of a fabrial replicating Regrowth, an application of the [[Surgebinding#Progression|Surge of Progression]].{{book ref|sa1|19}}

It is associated with the [[Order_of_Stonewards|Order of Stonewards]]

=== Heliodor ===
'''Heliodor''' is associated with the Essence of Sinew. They are used to Soulcast animal material, like meat and flesh.{{book ref|sa1|part=ars}}

Heliodors are used in the production of [[Fabrial#Warning fabrials|alerter fabrials]]. These fabrials can be used to detect a variety of stimuli, such as people and emotions, and give notice to its user.{{book ref|sa1|i|4}} The larger the heliodor, and as a result the more Stormlight that can be infused in it, the wider the fabrial's range is.{{book ref|sa1|part=ars}}

A heliodor was observed as part of a fabrial replicating Regrowth, an application of the [[Surgebinding#Progression|Surge of Progression]].{{book ref|sa1|19}}

It is associated with the [[Order_of_Bondsmiths|Order of Bondsmiths]]

They can be found in [[gumfrem]]s.{{book ref|sa3|10}}

== Obtaining ==
While Polestones are produced via mining, a significant source of them on Roshar is the harvesting of the [[gemheart]]s that grow inside [[greatshell]]s. Larger species of greatshell, like [[chasmfiend]]s, produce gemhearts of great size, which are incredibly useful in Soulcasting as a larger stone is less likely to break from the strain.{{book ref|sa1|13}} This trait however has led to many species of greatshells, such as the [[lanceryn]], to go extinct.{{book ref|sa1|36}} The exact method by which gemhearts are grown is not understood, though it is known to be caused by a leak from the [[Spiritual Realm]] into the [[Physical Realm|Physical]], and is analogous, though not identical, to the production of [[atium]] in the [[Pits of Hathsin]] on [[Scadrial]].{{wob ref|4678}}  Although they may have flaws, gemheart Polestones have virtually no impurities, unlike their conventionally mined counterparts.{{wob ref|6625}}

== Perfect Gemstones ==
'''Perfect gemstones''' occur when one of the Polestones forms without any flaws or imperfections which allows them to hold light indefinitely.{{book ref|sa3|i|13}} The money exchangers living in major cities of [[Shadesmar]] use perfect stones to store the Stormlight they use for currency.{{book ref|sa3|99}} The [[King's Drop]] is a perfect gemstone that has been held in the [[Thaylen Gemstone Reserve]] for over two hundred years without being renewed or losing Stormlight.{{book ref|sa3|i|13}} In addition to not leaking, a perfect gemstone can hold far more Stormlight than a normal gemstone of the same size could.{{book ref|sa4|87}} The [[Elsecallers]] were tasked with protecting perfect gems, including a ruby named [[Honor's Drop]].{{epigraph ref|sa3|83}} The [[honorspren]] have gathered many perfect gemstones in their stronghold [[Lasting Integrity]].{{book ref|sa4|87}} Most of the perfect gemstones in the Physical Realm are in the possession of the [[Ghostbloods]] due to their experiments in transporting [[Investiture]] offworld.{{book ref|sa4|13}}

Perfect gemstones have the capacity to hold [[Cognitive Shadow]]s in addition to spren, the latter of which they have a far larger capacity than normal gemstones--they can hold [[Herald]]s, the [[Unmade]], and even [[Fused]].{{book ref|sa3|120}}{{book ref|sa3|121}}{{book ref|sa4|14}} They could also capture some of the [[Dor]] or the sunlight from [[Taldain]].{{wob ref|15297}}

== Transfer ==
It is possible to transfer Light from a filled, small gemstone to a large and empty gemstone of its type by holding the filled gemstone to the empty one. This method of transfer is slow and inefficient; however, the [[Thaylen|Thaylens]] have discovered a more efficient way of transferring Stormlight from one gemstone to another. By using a tuning fork of a specific frequency, a person can touch an infused gemstone and then touch the fork to the empty gemstone for a rapid mode of transfer. With the Thaylen method, the type of Polestone does not matter, and light can be transferred from any type to any type. The decay rate is unknown, as is the distance the tuning fork can be brought before transfer is impossible.{{book ref|sa4|42}}

Surgebinders are also able to infuse Polestones regardless of the type, and can do so very quickly.{{book ref|sa4|44}}{{book ref|sa4|49}}

== Roshar Economy ==
{{for|Spheres}}
Gemstones form the basis for the Roshar economy. Gemstone weight is measured in kivs.{{book ref|sa4|42}} When used as currency, the gems are encased in glass [[spheres]]. Although the spheres are of uniform size, the gemstones inside are of three sizes.{{book ref|sa1|3}} In descending order of size (and value), these gem sizes are broam, mark, and chip.{{book ref|sa1|3}}
In addition, the value of the “sphere” is determined by the type of gemstone, which have different values as determined by their utility rather than their rarity.{{book ref|sa3|part=ars}}. Their relative value in descending order is as follows: emerald, sapphire,{{book ref|sa1|8}} ruby,{{book ref|sa3|7}} diamond, and garnet.{{book ref|sa1|17}} In addition, amethyst is one of the more valuable gemstones;{{book ref|sa2|9}} topaz{{book ref|sa1|30}} and zircon are amongst the least valuable.{{book ref|sa1|55}}

== Notes ==
;Footnotes
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; References
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{{file ref|name=Navani1|Navani1.jpg|text=Navani's Notebook: One}}

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