Paper Purse
 What is a paper purse? Folding a Purse Some Mathematics Another Paper Purse and Variations Paper Purse on the Internet Comments.
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What is a paper purse?
 ...... A paper purse is a nice folding, which can even be done by small children. The purse is folded from a rectangular sheet of paper in only a few steps and can be used instead of a real purse. It has two pockets.

Folding a Purse   top
 ...... Take a sheet of paper of the size A4 (8 1/2" x 11"). Find the centre line by folding the left side on the right side and by unfolding.

 ..... Cut off a strip of paper, so that you have a rectangle about double as long as broad.

 ...... Fold the paper on the four red lines upward, so that two corners meet on both sides.

 ...... It must look like this.

 ...... Fold the corners on the left and on the right on the red lines.

 ...... It must look like this.

 ...... Fold the left and the right sides, so that they meet at the centre. That means: Fold at the red lines.

 ...... It must look like this.

 ...... Fold backwards the upper and the lower strips, so that just the yellow triangles disappear.

 ...... It must look like this. Fold the paper backwards on the blue line.

 ......... The purse is nearly finished. You can already see the two pockets (pink).

 ...... Get out one triangle of a pocket. It is the lock of the purse.  The purse is finished.

Some Mathematics  top
 ...... If you unfold the purse, a pattern can be seen on the paper.  You can recognize the shape of the purse (green).
Obviously the shape of the paper determines the shape of the purse.
 ...... You can also start with a A4 paper. The purse gets a bad shape as you can see on the left.
You can also describe the first and last shape by formulas.

Here is an application of the formula  y:x=4:(2k-1).
In Germany a real purse has the shape of  DIN A like the identity card, which you can put in. These are the measurements sqr(2):1. If you give y:x=sqr(2), you get k=sqr(2)+1/2. This is about k=1,9. In the beginning of this page k=2 is chosen. This is the best shape of a sheet of paper to make the purse.

Another Paper Purse and Variations     top
Folded Square Purse
In the 1980s there was a folded purse for coins in fashion.
You can copy it using paper. It is a nice, but in the final stage not easily folded work.
 ...... ... This is the folded purse, closed and open.

Making of the folded purse
 ...... Draw a diagram of an open cube. Let the length of a square side be 7 cm (2 3/4 inches) e.g..

 ...... Before you form the cube, go over the coloured lines with an empty ballpoint and fold there. Distinguish between valley and mountain foldings.

 ...... Then form the cube and fix it with glue strips.  Fold along the diagonals - one after the other - once more and fold them down altogether to the basic square.

 ...... It must look like this. - The folded purse is finished.

There are some variants of this paper work.

Folded Purse Without Glueing
 ...... If you do this, you can avoid cutting off the corner squares.  Then you don't have to glue.  This is a sign of real origami.

 ...... The corner squares are coloured on both sides.

 ...... You can recognize the corner squares on the cube as two layers of isosceles rightangled triangles, which hang out at the diagonals. They hinder at opening and closing the purse, on the other hand, they are a nice ornament.

Carlo Wingerter offers a description on the internet (URL below).

Purse of a Tetra Pak Bag.
 ....... ...... You can cut off a Tetra Pak box (milk carton) at the top, so that a cube - open on top - is formed.  You scratch along four suitable diagonals and push the sides inside.  You also get a folded squared purse.

Hidden-Greetings Card
 ...... ...... This simple greeting card fits here. It has a square for writing.  On the square sides are four semicircles.  After you have written a text, you can hide it by semicircles folded inwards covering  each other partly.

Paper Purse on the Internet      top

German

Carlo Wingerter
Praktischer Geldbeutel aus Papier

Marion Kloskowski
Ein Portemonnaie basteln

Wawerko GmbH
Der Geldbeutel aus einer Safttüte

English

MR. CREATOR
How To Make an Easy Paper Purse  (Video Youtube)

the spruce Crafts
How to Make an Origami Purse

As far as I am informed, this paper purse is a rarity. I never found instructions somewhere.
I wrote this in 2003, when I made this web site. In meantime I got some emails from Germany: The paper purse is not so rare as I guessed.

Feedback: Email address on my main page