Golden Ratio Piedra Lumbre Piedra Lumbre II, 15x24, oil The Piedra Lumbre (shining stone) painting has a proportion that is approximately the golden ratio - or the golden mean, an irrational number, approximately 1.610287...., meaning continuing without end. As an irrational number it cannot be expressed as a ratio of two integers. I’ve done many paintings, with 10x16 dimension and a few at 15x24, and this 15x24, still with a ratio of 10/16 or 5/8. Note that these are two number in the Fibonacci sequence. 1,1,2,3,5,8, .... The radio of two consecutive numbers gets closer and closer to the golden mean as we progress through the sequence. Try calculating: 5/3, 8/5/ 13/8, 21/13,... The golden mean is related to the golden spiral, a form found in nature everywhere since it in fact represents how growth takes form (think sunflowers, ferns, tree branches, Nautilus Shell). The ratio is thought to be the most pleasing to the eye, perhaps because it is so pervasive and perhaps because it