Traditionally, a birthstone is associated with each month of the year. Diamond is the birthstone for the month of April.
The Gregorian calendar has poems matching each month with its birthstone. The poem for Diamond is :
“She who from April dates her years,
Diamonds shall wear, lest bitter tears
For vain repentance flow; this stone,
Emblem of innocence, is known.”
Diamond is the hardest known natural material where hardness is defined as resistance to scratching and is graded between 1 (softest) and 10 (hardest). Diamond hardness depends on its purity, crystalline perfection and orientation