Scarlet has laid a few double yolkers this summer. She usually lays normal but large eggs (~60 grams), and once a week, a double. Then the doubles got bigger. 76 grams. 91 grams. Then there was the lumpy shelled one, like it was a dinosaur egg, thick shelled. Then a few days later, another double-yolker, but it looked normal, 101 grams. No egg yesterday, the day before, one egg but in a more porous shell, without good colour. And now today, 109 grams, but with thin dent-able shell, and without its normal darker brown colour, density or bloom... I am thinking: make more calcium available to the hens, with oyster shell out fresh every day, and stick to the organic layer feed (even though it does have gluten. Scarlet is one of 2 sex link hens, same age, 1 coop, 1 nest box, but free ranging every day in the yard. Occasionally they are chased by my dog, but never caught. Thoughts?