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Tetrahedron (Halpern-Meier-Tetrahedron)
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Another custom Skewb mod by Tony Fisher with a complicated history.

This transformation of a skewb is also known as "Halpern-Meier-Tetrahedron" (short: HMT) after the two persons (Benjamin R Halpern and Kersten Meier) who first came up with this concept.
The patent behind the number given here dates back to 1981 and names Mr. Halpern as inventor.
In 1984 Aleksandr Ordynets filed a patent which covers the HMT (including trivial tips) and Trajbers Octahedron. This must be a case of parallel invention.
Tony Fisher is credited as inventor in this museum because he is the first person who is known to have actually produced one sample (by hand), which took place in 1991.
Edge length: 155 mm

To make the story even more confusing, in September 1981 Marko van Eekelen and Bernard van Houtum wrote a paper for their graduation. It describes drawings and solutions and mathematical descriptions of the puzzle. They never had a physically working puzzle at hand.

A very similar puzzle was presented as unrealized idea in 1982. Back then Uwe Meffert presented and equivalent puzzle in his famous catalogue. Sadly the "Pyraminx Magic Tetrahedron" (the name it beared back then) never went into production until Uwe Meffert started production of the pillowed variant "Jing's Pyraminx" (see the related entry) named after his wife.

Price Tracking Data

DISCLAIMER: The following table contains user-generated content. This information is collected to serve as a rough guideline and is certainly not complete and may not even be accurate. This information is filtered and carefully moderated, but incorrect information will inevitably find its way into the system. Always use your own judgement when buying or selling an item.

Sale Date Price (USD) Sale Type Condition Package Condition Notes Contributors Edit
Oct 22 2005 $551.58 eBay Auction Mint N/A None Darren Grewe



Thank you to the following people for their assistance in helping collect the information on this page: Geert Hellings, Gus.


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