They may well be eating too much calcium from the oyster shell.'Speckled' eggs can happen for several different reasons...very few, if any, of which are a 'problem'.
Can be caused by:
Excess or uneven pigment coating.
Excess or uneven cuticle(bloom).
Excess calcium deposits.
Porous eggs can appear speckled.
Some birds lay them consistently, some only once in awhile.
The pigment or bloom can change appearance when wet, then change back when dry again.
As long as bird is getting a good diet and is healthy in every other way, it is no cause for concern.
I was washing an egg today (had mud on it) and was only gripping it lightly when it exploded... it was an odd shaped egg... almost pointy. How do I make stronger-shelled eggs?The access calcium may be the cause especially if oyster shells are new and they eat more out of interest. They will figure it out otherwise. I rarely offer oyster shells unless I see an issue with soft egg shells. Many people leave it out as a free choice all year long.
Were the shell pieces a normal thickness?I was washing an egg today (had mud on it) and was only gripping it lightly when it exploded... it was an odd shaped egg... almost pointy. How do I make stronger-shelled eggs?