A two-trait Punnett Square has 16 boxes. The probability of a cross producing a genotype in any box is 1 in 16. If the same genotype is present in two boxes, its probability of occurring doubles to 1/8 (1/16 + 1/16).
November born individuals, are blessed with two ruling Birthstones, the revered Topaz and the gentle, healing Citrine. Topaz is a gemstone exhibiting an array of spectacular colors. The stone was believed to be symbolic of the Egyptian Sun God Ra, with its brilliant golden glow and fiery intensity.
The Gemstone Alexandrite is the color changing variety of the mineral Chrysoberyl. The June Birthstone, its color varies from red to green depending upon the light source. Synthetic corundums spiked with trace elements that yield an alexandrite-like color change are sold as alexandrite on the gemstone market.