Test Breeding Colors
Test breeding is a good way of bringing out the recessives that may be hiding. For Himalayans, it helps to show what your dominant colors carry. For example, you can breed a Lilac (most recessive) to a Black (most dominant) and their offspring should show what recessives the Black carries. If you get dilutes, you know your Black is a dilute carrier or Dd. If you get chocolates or lilacs, you know your Black is a chocolate carrier or Bb. This, of course, is not an exact science and would take a much larger pool of breedings to accurately determine if the Black is NOT carrying a recessive should you only get blues or chocolates as the variety other than black.
Your dilute colors, Blue and Lilac, may require test breeding to accurately determine what color it actually is. If your Blue is light or, conversely, Lilac dark, test breeding may be necessary to determine the genotype. In this particular case, I would recommend breeding to a chocolate as it limits the colors you can produce. If it is a lilac, you will only get chocolates and lilacs. If it is a blue, you will get blues and maybe even blacks.
Your dilute colors, Blue and Lilac, may require test breeding to accurately determine what color it actually is. If your Blue is light or, conversely, Lilac dark, test breeding may be necessary to determine the genotype. In this particular case, I would recommend breeding to a chocolate as it limits the colors you can produce. If it is a lilac, you will only get chocolates and lilacs. If it is a blue, you will get blues and maybe even blacks.