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 Post subject: GO Faceting Design Competition 2016
PostPosted: Thu Mar 10, 2016 2:10 pm 
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Gemology Online Faceting Design Competition 2016


Welcome to the Gemology Online 2016 Faceting Design Competition! Since I did a very poor job of advertising last year's competition and had to cancel it, I've gone ahead and redone the competition for this year.


*I will be submitting designs for fun, but am removing myself from the competition, since that would be a massive conflict of interest.




Categories:

The competition has three categories of design specifications; each category has different requirements for acceptable design. Within each category, there will be two finalists. All categories will be scored exclusively according to an open poll, with more detail given below.

Please note that all designs will require a test cut.



"Introduction":
  • This category is designed to encourage new designers or new cutters to submit a faceting diagram of their own, particularly if they have limited experience with GemCAD or designing in general. Submit literally whatever the hell you want, as long as it's a new design!
  • A photographed test cut in the designer's chosen material will be required for submission.
  • Designs may not have more than 201 facets or 31 tiers (including table).
  • Designs may be written for any material.
  • Designs must be reproducible entirely in a meetpoint manner.
  • Designs must have a level girdle on both the crown and pavilion side, but the girdle is not required to be straight.
  • There are no other restrictions on design.
  • Designs will be scored entirely according to an open poll. Further information about the poll is listed below.
  • Due to the particularly non-restrictive nature of this category, prizes offered will be slightly less and lower-value than for the other two categories.



"Blackout":
  • This category is designed to encourage faceters to develop designs that work for iron-bearing pyralspite garnets (dark red), iron-bearing spinels (dark purple), extremely iron-bearing sapphires (dark blue), chrome-bearing open-C tourmalines (dark green), and chrome diopside (dark green). When overly dark, these materials are extremely cheap, and the ability to convert them to saleable cut stones with a decent representation of color is a skill that will greatly serve the cutter.

    All of those materials are notorious for having the so-called "blackout effect", a particularly annoying flavor of darkness that responds poorly to traditional attempts to raise light output. It's an expected function of the Beer-Lambert Law, which basically states that as the concentration of a chromophore increases, the stone absorbs more light, turning it black. These stones are traditionally cut by intentionally windowing the stone or by using a small number of facets with a large area on each facet. The goal of this category is to produce a design for these "blackout" materials, such that the color of the material is readily apparent, and such that the finished stone does not look nearly totally black in all lighting conditions.
  • The designer should write a design for one of the following materials:
    • Dark pyralspite garnets with a typical over-saturated red, purple, reddish-brown, or similar color.
    • Dark spinels with an over-saturated purple color, similar to characteristic Tanzanian spinels.
    • Dark sapphires with an over-saturated blue color, similar to characteristic Australian sapphires.
    • Dark tourmalines with an over-saturated green color and an open C axis, similar to typical chrome tourmaline.
    • Dark chrome diopside.
  • A photographed test cut in the designer's chosen material will be required for submission. Designers are strongly encouraged to take two photographs, one of the rough material placed on a mirror ("small mirror test" shot), and one of the finished stone. Videos of the stone are HIGHLY encouraged as well.
  • Designs must be reproducible entirely in a meetpoint manner.
  • There are no other restrictions on design.
  • Designs will be scored entirely according to an open poll. Further information about the poll is listed below.



"Rainbowlicious":
  • This category is designed to encourage faceters to develop designs that maximize the dispersion of a given material. While the common thought is that dispersion is maximized with a deep pavilion and a tall crown, trial-and-error experimentation has shown that this is not always true, and that dispersion can be maximized with very deep as well as very shallow designs. The goal of this category is to produce a design that has as much dispersion as possible given the material.
  • The designer should write for a material with comparatively high dispersion and refractive index. Using one of the following materials is highly recommended (BUT NOT REQUIRED!), as they should still be at least somewhat readily available. Remember that lighter-colored materials will show off their dispersion better!
    • Mali garnet, RI = 1.78, dispersion = 0.057
    • Sphene, RI = 1.81, dispersion = 0.051
    • High zircon, RI = 1.93, dispersion = 0.039
    • Sphalerite, RI = 2.40, dispersion = 0.156
    • Zincite, RI = 2.01, dispersion = 0.127
    • Gadolinium-gallium garnet, RI = 2.03, dispersion = 0.038
    • Cubic zirconia, RI = 2.16, dispersion = 0.060
    • Lithium tantalate, RI = 2.18, dispersion = 0.128
    • Lithium niobate, RI = 2.30, dispersion = 0.123
    • Strontium titanate, RI = 2.41, dispersion = 0.109
    • Moissanite, RI = 2.62, dispersion = 0.104
    • Rutile, RI = 2.62, dispersion = 0.312 (holy crap!)
  • A photographed test cut will be required for submission. Designers must use the same material that they have listed on the design as the intended material. Cutters are also highly encouraged to use a professional photo that demonstrates the stone's dispersion.
  • Want to submit a video of the finished stone? I'll put it up here so people can really see the dispersion.
  • Designs must be reproducible entirely in a meetpoint manner.
  • There are no other restrictions on design.
  • Designs will be scored entirely according to an open poll. Further information about the poll is listed below.



Scoring:

Scoring via open poll:
There will be an open poll for 1 month after the submission deadline, allowing anyone to vote for their favorite design. Each competition entry will be assigned an anonymized ID and all identifying information will be stripped. If a competitor discloses the anonymized ID associated with his or her designs, that competitor will be disqualified from the competition. This is to ensure that people vote based on design, and not based on the author.

Each choice in the poll will be labelled by anonymized ID. Each will show the entire anonymized design, with two animated .gif images. The first will be a 300x300 GemRay rendering of a clear stone, while the second will be a 300x300 GemRay rendering as a pink-green test. Both will be rendered using a 30* tilt window and a 10* head shadow. For the "Extinction" category, the cutter's intended material will be used for the renderings.

Each design will also be listed with the photograph(s) required by the particular category it has been submitted to.

This poll will operate under an “top 3” system. Voters will numerically rank their favorite 3 designs in each category, ranking their favorite design as “1”, their next-favorite as “2”, and their third-favorite as "3". Voters may vote in all three categories. All votes are weighted the same.

If a design earns more than 50% of the total votes in a category, that design and the design with the second-highest number of votes will become the two finalists in that category. If no design earns more than 50% of all votes, then a runoff process begins. The design with the lowest number of “1” votes will be removed from the running. Ballots with that design listed as #1 will have their votes distributed to the second preference listed, #2. This process is repeated until one design holds more than 50% of the total votes in the category.

Each of the six finalists will receive prizes of rough, and possibly other items. Among the six finalists, the design with the greatest total number of votes will be the grand prize winner - the grand prize winner will receive a much larger parcel of rough and other related items.




Submissions:

How to Enter:
  • To submit your design, send a copy of the diagram (GemCAD files are preferred) and photo(s) of the test cut stone to faceting101@gmail.com. In the subject line, include your name and which category your entry is for. Please indicate what material the design is intended for.
  • All submitted designs will be re-drawn in GemCAD. This is done to ensure that all designs will be written using a standardized convention, preventing voters from using naming and organization conventions to recognize a specific person’s design.
  • All entries will be anonymized by being assigned a number in order of submission.
  • Each competitor may enter a maximum of one design per category. Competitors may enter one or more categories, for a total of three entries.
  • A single design may only be submitted to one category.
  • A single designer can become the finalist in multiple categories.
  • All designs submitted to the competition will be entered into the Gemology Project after the contest, in a "Faceting Design Contest 2016" section. Full credit will be given to the author of the design.
  • By submitting an entry, you agree that the design you submit is freely in the public domain.

Design Rules:
  • All designs must have a faceted girdle. The girdle is not required to be level (see Robert Strickland’s "No Stinkin’ Badges" design from the 2013 competition). However, the girdle must have a continuous crown and pavilion line.
  • Diagrams which require the use of a CAM preform will be accepted.
  • All designs must be able to be generated in strict meetpoint fashion. Diagrams which use floating facets or step facets, diagrams that require measurement, and diagrams which cannot be recreated in meetpoint fashion will not be accepted.
  • If your design cannot be generated in strict meetpoint fashion, you will be informed on where and how the design cannot be reproduced, and you will be allowed to resubmit after corrections.
  • No previously-published designs, or designs previously made available to any other individual, may be submitted.
  • Designs that are considered to have gross defects (substantial tilt windowing, substantial head-on window, etc.) will not be accepted.
  • There is no advantage or disadvantage to voting earlier or later in the voting period.
  • A test-cut of your stone is 100% mandatory, with photographs for proof as indicated in each category.

Deadlines:
  • March 15th, 00:00 CST - Rules finalized and competition open for submission
  • May 31st, 23:59 CST - Submission period for designs ends.
  • June 1st, 00:00 CST - Voting period begins.
  • June 15th, 23:59 CST - Voting period ends.
  • June 16th - Finalists and Grand Prize winner announced.



Prizes:

Donors:
  • Arya Akhavan

Grand Prize:
All of the following items (donated by several people):
  • A piece of synthetic, highly dichroic bicolor quartz with distinct green and yellow zones. Yes, it's bicolor AND dichroic.
  • Madagascar blue apatite
  • Indian iolite
  • Pakistani topaz, faded on windowsill for 2 months
  • Assorted bits of synthetics

Finalist Prizes:
The finalist prizes will be distributed to the runners-up. All donated prizes will be combined into a common pool and redistributed as evenly as possible among the finalists. The Grand Prize-winning entry will not be eligible for Finalist prizes; however, a designer with multiple designs may win both the Grand Prize for one design in one category, and a finalist prize for a different design in a different category.
  • A random, smaller assortment from Arya's personal stock.


Last edited by Faceting 101 by Arya on Sat Mar 12, 2016 5:25 pm, edited 1 time in total.

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 Post subject: Re: GO Faceting Design Competition 2016
PostPosted: Fri Mar 11, 2016 6:16 pm 
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Cool! Maybe it's time to finally figure out GemCad... though I think all the Warcraft-related design names have been taken by someone...


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 Post subject: Re: GO Faceting Design Competition 2016
PostPosted: Fri Mar 11, 2016 7:40 pm 
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Christa wrote:
though I think all the Warcraft-related design names have been taken by someone...

Sux4u :P I took some Wildstar ones too!

But nah, there's still plenty of stuff left.


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 Post subject: Re: GO Faceting Design Competition 2016
PostPosted: Fri Mar 11, 2016 9:31 pm 
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Christa wrote:
though I think all the Warcraft-related design names have been taken by someone...

Hehe. It's appropriate because there's a lot of grinding involved!

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 Post subject: Re: GO Faceting Design Competition 2016
PostPosted: Sat Mar 12, 2016 12:06 am 
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You could always try names from EVE Online, plenty of good ones in the wiki site... and plenty of minerals in the game too.

It's a pity that the only "Extinct" materials I have are prehnite and smoke chalcedony, would have liked to try making a dome design that works in them as well as iron darkened stones.
Botryoidal and polycrystalline minerals display their own special kind of pain with the growth fibres blurring any fire that the cut stone could have.


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 Post subject: Re: GO Faceting Design Competition 2016
PostPosted: Sat Mar 12, 2016 9:37 am 
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Awesome! Might be a reason I try and learn GemCad :)


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 Post subject: Re: GO Faceting Design Competition 2016
PostPosted: Sat Mar 12, 2016 11:43 am 
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Extinction isn't just a function of iron, the design has a lot to do with it even in very open color stones. I see plenty of design, some even in the GO project with too much extinction in them for me to consider cutting. Dark stones will always be dark stones, it's best to avoid the temptation of buying them as rough in the first place.

This is of course just my opionion and not meant for anyone else to pay any attention to or be offended by.

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 Post subject: Re: GO Faceting Design Competition 2016
PostPosted: Sat Mar 12, 2016 2:20 pm 
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Faceting 101 by Arya wrote:
Christa wrote:
though I think all the Warcraft-related design names have been taken by someone...

Sux4u :P I took some Wildstar ones too!

But nah, there's still plenty of stuff left.


Arya, maybe you should have a category for best name :-)


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 Post subject: Re: GO Faceting Design Competition 2016
PostPosted: Sat Mar 12, 2016 5:30 pm 
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Precision Gem wrote:
Extinction isn't just a function of iron, the design has a lot to do with it even in very open color stones. I see plenty of design, some even in the GO project with too much extinction in them for me to consider cutting. Dark stones will always be dark stones, it's best to avoid the temptation of buying them as rough in the first place.

This is a very good point! It's not necessarily just iron, but also chromium and other chromophores.

There are several distinct phenomena when it comes to stones turning dark. The first is absorbance (too much chromophore), which is what you see with these really dark red and green stones. The second is head shadow, when the viewer's head blocks some of the light entering the stone. The third is extinction, a function of light reflection through the stone (can be tested in GemCAD by setting head shadow to 0). Windowing causes light leakage and loss, but that's more of a loss of brilliance than an active darkening effect. There may actually be more phenomena involved, but that's what I can think of offhand.


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 Post subject: Re: GO Faceting Design Competition 2016
PostPosted: Sat Mar 12, 2016 7:41 pm 
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I wasn't really referring to the material, but rather the design. Someone recently posted a tourmaline and morganite, to me, at least from the photos, the stones had a lot of extinction. The extinction wasn't due to iron or any other element, but rather the design. A good design is more than just connecting meet points.

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 Post subject: Re: GO Faceting Design Competition 2016
PostPosted: Sat Mar 12, 2016 9:44 pm 
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Precision Gem wrote:
I wasn't really referring to the material, but rather the design. Someone recently posted a tourmaline and morganite, to me, at least from the photos, the stones had a lot of extinction. The extinction wasn't due to iron or any other element, but rather the design. A good design is more than just connecting meet points.

If you're talking about Wybee's pictures, if I'm correctly remembering what he told me, those are actually head shadow (technically camera, not head), from sticking the camera really close up to the stone. Not actually a function of the design :)


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 Post subject: Re: GO Faceting Design Competition 2016
PostPosted: Sun Mar 13, 2016 10:43 am 
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I don't know, the extinction in the photos looks very much like the extinction in the ray trace images.

Image

Image

Image

Image

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 Post subject: Re: GO Faceting Design Competition 2016
PostPosted: Sun Mar 13, 2016 12:55 pm 
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I stand corrected :) I don't think the first one matches up well, but the second one does.


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 Post subject: Re: GO Faceting Design Competition 2016
PostPosted: Sun Mar 13, 2016 1:18 pm 
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I don't always put a lot of stock in the gem trace programs. I have a few designs I cut often that perform very well with real stones, but in the ray trace programs don't. Photographing gems is also very difficult. Some stones can look really nice in the hand, but are just very camera shy.

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 Post subject: Re: GO Faceting Design Competition 2016
PostPosted: Sun Mar 13, 2016 1:39 pm 
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Precision Gem wrote:
I have a few designs I cut often that perform very well with real stones, but in the ray trace programs don't.

You know the best example of this? Portuguese cuts. They look AWFUL in raytrace, but really nice in person. It's insane. The exact opposite happens with simple designs that have low angles for thin, high RI material. They look really nice in raytrace but SUCK in real life.


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