On May 9, 2012 Mark Frauenfelder publishes on BoingBoing the photograph of a strange coin. He received it during a visit to the Stupid Fun Club in Berkeley. (1)  Assuming that it hides something, Mark writes:

Here’s a puzzle [...] What is the secret message?

Having recently dealt with the study of Llull’s wheels, used in the 16th century to create a strange magical book, I formulate the hypothesis that the various “marks” on the seven concentric circles define specific angles, each connected to a letter of the alphabet.

Starting from the picture, I record the coordinates of each notch, in order to plot an electronic version of the coin in R.

library(plotrix)
distance<-function(x1,y1,x2,y2) { sqrt((x2-x1)^2+(y2-y1)^2) }

#Coordinates of notches on the JPG file
x<-c(103,31,115,75,40,101,70,75)
y<-c(22,105,49,34,79,85,96,90)
#Inversion of the y-axis to plot it correctly
y<-150-y
#Plotting points at the position of each notch
plot(x,y,xlim=c(0,150),ylim=c(0,150),asp=1)
#Plotting circles and segments
for(i in 1:8)
{
	draw.circle(75,75,distance(75,75,x[i],y[i]),border=“lightgray”)
	segments(75,75,x[i],y[i])
}

By adding the letters from A to Z around the outer circle, it is easy to identify the correspondence between the eight segments and related letters.

#Letters added to the graph
for(i in 1:length(alpha))
    text(75+70*cos((pi*2)*((33.5-i)/26)),
	 75+70*sin((pi*2)*((33.5-i)/26)),
         LETTERS[i])
 

Download the R script to create this image.

By reading them in order, from the segment corresponding to the outer circle to the innermost, the letters form the word CREATION. (2) .

Download the R script to create this image.

When I return to BoingBoing I discover that Dan got it before me. Kudos to him!

Notes