Le Grand K, an alloy that is the international standard for the kilogram, has been losing weight over the years. Why?
Dr. Richard Steiner of the National Institute of Standards declared:
- "Relative to the average of all the sister copies made over the last 100 years you could say it is losing [mass], but by definition it can't. So the others are really gaining mass."[1]
"By definition" refers to how Le Grand K is still defined as one kilogram, no matter how much weight it actually loses.