Editing Gemstone (section)

=== Creation process ===
There are two main categories for creation of these minerals: melt or solution processes.<ref name="Weldon"/>

==== Verneuil flame fusion process (melt process) ====
[[File:Verneuil process diagram.svg|thumb|Verneuil furnace]]
The flame fusion process was the first process used which successfully created large quantities of synthetic gemstones to be sold on the market.<ref name="Scheel-2000">{{Cite journal |last=Scheel |first=Hans J |date=2000-04-01 |title=Historical aspects of crystal growth technology |url=https://www.sciencedirect.com/science/article/pii/S0022024899007800 |journal=Journal of Crystal Growth |language=en |volume=211 |issue=1 |pages=1–12 |doi=10.1016/S0022-0248(99)00780-0 |bibcode=2000JCrGr.211....1S |issn=0022-0248 |access-date=April 15, 2023 |archive-date=April 15, 2023 |archive-url=https://web.archive.org/web/20230415031315/https://www.sciencedirect.com/science/article/pii/S0022024899007800 |url-status=live }}</ref> This remains the most cost effective and common method of creating corundums today.

The flame fusion process is completed in a Verneuil furnace. The furnace consists of an inverted blowpipe burner which produces an extremely hot oxyhydrogen flame, a powder dispenser, and a ceramic pedestal.<ref name="Read-1999">{{Cite book |last=Read |first=Peter G. |title=Gemmology |date=1999 |publisher=Butterworth-Heinemann |isbn=0-7506-4411-7 |oclc=807757024}}</ref> A chemical powder which corresponds to the desired gemstone is passed through this flame. This melts the ingredients which drop on to a plate and solidify into a crystal called a ''boule''.<ref name="Read-1999"/> For corundum the flame must be 2000&nbsp;°C. This process takes hours and yields a crystal with the same properties as its natural counterpart.

To produce corundum, a pure aluminium powder is used with different additives to achieve different colors.<ref name="Read-1999"/>

* Chromic oxide for ruby
* Iron and titanium oxide for blue sapphire
* Nickel oxide for yellow sapphire
* Nickel, chromium and iron for orange sapphire
* Manganese for pink sapphire
* Copper for blue-green sapphire
* Cobalt for dark blue sapphire

==== Czochralski process (melt process) ====
In 1918 this process was developed by J. Czocharalski<ref name="Read-1999"/> and is also referred to as the "crystal pulling" method. In this process, the required gemstone materials are added to a crucible. A seed stone is placed into the melt in the crucible. As the gem begins to crystallize on the seed, the seed is pulled away and the gem continues to grow.<ref name="Weldon"/> This is used for corundum but is currently the least popular method.<ref name="Scheel-2000"/>

==== Flux growth (solution process) ====
The flux growth process was the first process able to synthesize emerald.<ref name="Lefever-1982"/> Flux growth begins with a crucible which can withstand high heat; either graphite or platinum which is filled with a molten liquid referred to as flux.<ref name="Scheel-2003">{{Cite book |last=Scheel |first=Hans |title=Crystal Growth Technology |publisher=John Wiley & Sons |year=2003 |isbn=9780470871683}}</ref> The specific gem ingredients are added and dissolved in this fluid and recrystallize to form the desired gemstone.This is a longer process compared to the flame fusion process and can take two months up to a year depending on the desired final size.<ref name="Arem">{{Cite web |last=Arem |first=Joel |title=Understanding Gem Synthetics, Treatments, And Imitations, Part 4: Synthetic Gemstone Guide |website=International Gem Society |url=https://www.gemsociety.org/article/understanding-gem-synthetics-treatments-imitations-part-4-synthetic-gemstone-guide/ |access-date=March 30, 2023 |archive-date=March 22, 2023 |archive-url=https://web.archive.org/web/20230322211822/https://www.gemsociety.org/article/understanding-gem-synthetics-treatments-imitations-part-4-synthetic-gemstone-guide/ |url-status=live }}</ref>

==== Hydrothermal growth (solution process) ====
The hydrothermal growth process attempts to imitate the natural growth process of minerals. The required gem materials are sealed in a container of water and placed under extreme pressure. The water is heated beyond its boiling point which allows normally insoluble materials to dissolve. As more material cannot be added once the container is sealed, in order to create a larger gem the process would begin with a "seed" stone from a previous batch which the new material will crystallize on. This process takes a few weeks to complete.