lol Usually if I toss them one of those little pints of blackberries, the next day I get at least one egg with purple/lavender freckles on it! I have also noticed large quantites of live mealworms will affect the color of the egg shells too. It tends to make them richer in color.
Well I failed on my first attempt at meal worm farming, but I have my tubs ready to stock again. I had them ready for a month. LOL Wonder if they help with purple? Guess I'll find out.
BTW....I didn't start off with Marans eggs. I breed Marans roos to hens I thought would produce pink. I have pink EE hens too, so between those I worked at getting a dark pink without it looking brown. Add the blue and you get lavender.