Date: Mon, 13 Feb 95 01:05:00 WET
From: Martin Schoenert <Martin.Schoenert@math.rwth-aachen.de >
~~~ Subject: Re: The Pyraminx Lost

I have never seen the Pyraminx. I wonder if somebody could tell me
the Pyraminx is correct?

I am fairly certain that the Pyraminx is a regular tetrahedron. In the
solved state each of the four faces shows only one of the four colours.

I think the Pyraminx is cut along 8 planes, two planes perpendicular to
each of the four heights (i.e., the four lines that connect a corner with
the center of the opposite face). I think for the Pyraminx those planes
intersect the height at about 2/5 and 3/5 of the length of the height.

Those planes cut the Pyraminx into 15 pieces (1 central piece, 4 corners,
4 inner pieces, and 6 edes), which are all visible. Each face is cut
into 10 facelets by them as follows.

```               +
/ \
/   \
/     \
/       \
/         \
+-----------+
/ \         / \
/   \       /   \
+-----+-----+-----+
/ \     \   /     / \
/   \     \ /     /   \
/     \     +     /     \
/       \   / \   /       \
/         \ /   \ /         \
+-----------+-----+-----------+
```

The Pyraminx Star was descibred as a Pyraminx without the centers.
So I guess each face of the Pyraminx Star looks as follows.

```               +
/ \
/   \
/     \
/       \
+---------+
/ \       / \
/   \     /   \
/     \   /     \
/       \ /       \
+---------*---------+
/ \       / \       / \
/   \     /   \     /   \
/     \   /     \   /     \
/       \ /       \ /       \
+---------+---------+---------+
```

The Pyraminx Snub was described as a Pyraminx without the tips.
So I guess each face of the Pyraminx Snub looks as follows.

```   +-----------+
/ \         / \
/   \       /   \
+-----+-----+-----+
\     \   /     /
\     \ /     /
\     +     /
\   / \   /
\ /   \ /
+-----+
```

I have no idea what Pyraminx Senior and the Pyraminx Master look like.

Have a nice day.

Martin.

```-- .- .-. - .. -.  .-.. --- ...- . ...  .- -. -. .. -.- .-
Martin Sch"onert,   Martin.Schoenert@Math.RWTH-Aachen.DE,   +49 241 804551
Lehrstuhl D f"ur Mathematik, Templergraben 64, RWTH, 52056 Aachen, Germany
```