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What color are dark Marans eggshells?

Dark Marans are a breed of chicken known for laying very dark brown eggs. The exact shell color can range from chocolate brown to almost reddish, making Marans eggs easy to distinguish from other brown egg layers.

Typical Colors

The dark brown color comes from protoporphyrin, a pigment deposited on the eggshell as it forms within the hen. Here are some of the common colors for Dark Marans eggshells:

  • Chocolate brown
  • Deep reddish brown
  • Dark copper
  • Reddish chocolate

There can be some variation between individual hens. But in general, a quality Dark Marans will lay eggs with a very dark brown shell.

What Causes the Dark Shells

Marans chickens originate from the port town of Marans, France. Through centuries of selective breeding, the birds developed the ability to lay dark brown eggs. The gene responsible is known as the protoporphyrin gene.

All eggs start out white inside the hen’s oviduct. As the shell forms, proteins and pigments are deposited to give it color. In most breeds, the main pigment is oocyanin, which results in white or blue eggshells.

In Marans and other brown egg layers, biliverdin is the main pigment. It produces light to mid brown shells. The Marans also produce a high amount of protoporphyrin, which is a reddish-brown pigment. The more protoporphyrin, the darker the shell will be.

How Dark is Too Dark?

Some Marans may occasionally lay eggs that are very dark reddish-brown or even purplish-black. While this may seem impressive, it can indicate a defect.

Eggshell color is also influenced by the hen’s diet and health. A very dark, abnormal shell can mean the pigment was not evenly distributed when the shell formed. These eggs are more prone to cracks and breakage.

The ideal Marans egg should be a deep chocolate brown, with an even, smooth surface. If eggs are consistently too light or too dark, it points to a need to improve breed quality.

Do Shells Darken with Age?

Marans hens tend to lay their darkest eggs once reaching full egg production, at around 7-8 months old. But the shell color remains fairly constant over the life of the hen.

As eggs age, the cuticle or outer covering on the shell starts to erode. This can make the brown color appear slightly lighter or faded. But a true Marans egg will never turn into a light brown or cream color.

Differences Between Hen Feathers

Within the Dark Marans breed, hens can have black, silver-cuckoo, or golden-cuckoo feather patterns. The feathers do not affect egg color. But the colors make it easy to identify hens in a mixed flock.

Variety Feather Pattern
Black Entirely black plumage
Silver-Cuckoo Barred black and white pattern
Golden-Cuckoo Barred black and golden pattern

How Marans Compare to Other Brown Egg Layers

While other chicken breeds lay brown eggs, Marans are the undisputed champions. The dark chocolate brown shells stand out clearly from other shades of brown.

Breed Shell Color
Marans Dark chocolate to reddish-brown
Barnevelder Medium to dark brown
Welsummer Terracotta or speckled brown
Penedesenca Dark brown
Orpington Light to mid brown

Tips for Getting Dark Eggs

Here are some tips for producing those coveted, chocolate-colored Marans eggs:

  • Obtain birds from reputable Marans breeders.
  • Choose lines known for producing dark eggs.
  • Feed a diet rich in xanthophylls like corn or alfalfa.
  • Supplement with antioxidants like vitamin E.
  • Avoid stressors that disrupt pigment deposition.
  • Cull hens that lay abnormal or light-colored eggs.


The hallmark of a quality French Marans hen is the ability to lay a dark chocolate or deep copper-colored egg. The dark pigment comes from protoporphyrin deposited on the shell. While the degree of darkness can vary, the shells should be a deep, even brown with no streaking.

With selective breeding and proper diet, Marans hens will reliably produce eggs with that signature colorful shell. When it comes to brown eggs, no other breed can lay as dark as a Marans!