My friend and I are trying to make 'ninja black eggs' which are essentially hollowed eggs filled with powdered material.

We have two questions:

  1. Is there a way to thicken the egg shell? My current idea is basking the eggs in some-sort of calcium. Would this work, or is there a better way?

  2. How can we make the eggs black? We've tried making egg dye; and we have used 1 tsp of red, and 1/2 tsp of blue, but somehow the eggs turned brown.

  • because red and blue yield brown (last sentence of this section) Aug 18 '11 at 12:33
  • I thought they make purple... Maybe I suck at art.. Aug 18 '11 at 13:24
  • 3
    Ninja black eggs? For IRL Angry Birds, perhaps?
    – hairboat
    Aug 18 '11 at 14:19
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    But I do have a suggestion. Forget the egg shells. Fill a balloon with your powder and inflate to appropriate size. Then cover the balloon with your material (wet clay, paper mâché, melted chocolate, etc.). then pop the balloon with a pin s your coating sets. Fill in the pin hole if needed. Then you can make your "egg" from whatever you want. Use black spray paint to make it black.
    – yossarian
    Aug 21 '11 at 20:12
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    Check out UkrainianGiftShop.com for all sorts of egg dyes, including black. (Note that their dyes are not food-safe, though, so you'll have to discard the innards after dyeing the eggs.) They also sell gadgets for blowing out the eggs through a single hole.
    – Marti
    Apr 7 '13 at 15:20

Why do you need to thicken the shells? Some bird's eggs have thicker walls than others, and it also seems that younger hens form thicker shells than older ones. However, it is doubtful that a thicker eggshell is available commercially. Your best bet may be to poke holes in the eggs, let them drain and dry, and then paint them with a strengthening varnish. A water-based polyurethane maybe? You should probably color them first, and then varnish them.

You can buy black food coloring. Buy it online if you haven't seen it at your local stores. You will probably have to use more than suggested to get full, deep color coverage. If that doesn't work, you could try clothes dye, Rit is a good brand, but I don't see evidence it is recommended for use on eggs. However, since it appears you won't be eating the eggs, just throwing them at each other, it is probably safe, and you could dye a bunch of eggs at once.


You can't use different colors to make black. If you combine the primary colors, red, by blue, and yellow you will get brown, but black is the absence of color. Try black egg dye.

The problem I think is that the albumen of the egg is a translucent material and adding food coloring is also a translucent material. So effectively you are going to get a strong yellow color from the opaque yolk, and that is what will be predominant, so it makes sense you are getting brown. Adding translucent colors to opaque yellow will get a brown. Think about adding milk to coffee. If you add whole milk, you get a lighter brown. If you add skim milk, which has more water, you get something akin to gray.

So what you want is some sort of additive that is opaque. Maybe squid ink.

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