https://www.goldennumber.net/nautilus-spiral-golden-ratio/
Is the Nautilus shell spiral a golden spiral?
February 8, 2014 by Gary Meisner 65 Comments Nautilus shell spirals may have phi proportions, but not as you may have heard.
The Nautilus shell if often associated with the golden ratio. There is a fair amount of confusion, misinformation and controversy though over whether the graceful spiral curve of the nautilus shell is based on this golden proportion. Some say yes, but offer no proof at all. Some show examples of spirals, but incorrectly assume that every equi-angular spiral in nature is a golden spiral. Several university math professors say no, but they only compared the nautilus spiral to the spiral created from a golden rectangle. Another university professor says no, but only measured height and width of the entire shell. Let’s look at this objectively and solve this mystery and debate."
"The golden spiral is then constructed by creating an arc that touches the points at which each of these golden rectangles are divided into a square and a smaller golden rectangle. "
More at link!
I wonder how a nautilus quilt would look?
