Shells from snails often can be derived from a logarithmic spiral, which is given here. In such a spiral the radius is increasing exponentially with increasing revolutions.
- Logarithmic spiral
In this case, in addition to the exponentially increasing radius, the spiral is increasing exponentially in a direction perpendicular to its revolutions.
Logarithmic spiral
Nice snails can be constructed by increasing the thickness of the red helix (again in an exponential way).
Simple snail
By subtracting a slightly smaller structure, the shells become hollow.
Open snail
Sectioned snail