I don't recall who offered it, but this "dinosaur eggs" plan first came to artsednet back in '96 or '97. I think a search of the artsednet archives for something like "hollow plaster eggs" may be helpful, but it appears that artsednet search is out of commission at the moment.
This is the rough idea:
You need 6-8 inch helium quailty balloons; 1 liter soda bottles (dry) with caps; premeasured plaster of paris (us an 8 oz paper cup about half full) and water (read plaster instructions), large wash tub half filled with water.
1. Put dry plaster of paris in the bottle, then add the correct abount of water to the bottle, cap then shake to mix.
2. Carefully stretch lip of balloon over uncapped mouth of soda bottle, then pour plaster into balloon. Work balloon lip off the bottle mouth, add air to the balloon to the size you like (biggest is NOT best!), then tie the balloon.
3. VERY GENTLY pass the liquid plaster filled balloon from hand to hand, so that the pplaster moves around to all area of the inside of the balloon. DO NOT BUMP OR SQUEEZE as you continue to pass from hand to hand, making sure every inside surface is repeatedly coate dwith plaster.
4. After 15-20 minutes of EXTREMLY CAREFULL movement, the plaster will begin to get warm, as it solidifies. Continue SUPER SOFT handling for another minute or two, until the liquid plaster is no longer moving. Float the balloon in the tub of water to continue its curing process.
5. The next day, remove the hardened plaster from the tub, and cut the balloon off. It is still fragile at this point, but will cure in another day or so.
6. Decorate with pencil, markers and/or watercolors. I like to draw portraits on them, or create colorful patterns.
Good luck, Mark
From: Sandy [mailto:firstname.lastname@example.org]
Sent: Wednesday, October 23, 2002 5:03 PM
To: ArtsEdNet Talk
Subject: Dinosaur Eggs - recipe
Does anyone have or remember the recipe for dinosaur eggs? Want to make
them to bury in my dig for the kinders to uncover -- by Friday!
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