Egg shells are 97% calcium carbonate and 3% calcium phosphate.
You want to char the egg shells for calcium. Uncooked for phos.
Mine gets that reaction with egg shells but not animal bones
Here I just started a wcap with chicken bones.
1. I removed all the meat. Boiled the bones for 40 min.
2. Then washed the bones with soap and hot water.
3. Then I boiled the bones for 20 min
4. Then laid out the bones on a baking sheet and set them outside for 12 days to dry out until the middle sized ones were able to easily snap. Temps here have been 85°-.95° F during the day.
I didn't takes pics of boiling and cleaning.
After the bonws had dried out
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5. I warmed up the bbq as hot as i could get it. Almost 500°. F Put the baking sheet of bones on the bbq for 2 1/2 hours. For the first 30 minutes there was tons of smoke. DO NO DO THIS INDOORS! Like with an oven or skillet.
It smelled just like burnt charred food.
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6. Then easily pulverized the bones with a mortar and pestle.
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7. I poured the bone meal into a food grade plastic bottle and added the vinegar. ( I gave away all my jars and haven't got new ones yet).
3/4 cup bone meal : 3 3/4 cups vinegar
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8. I sealed the lid with an airlock to allow co2 to escape but not to let any contaminants get into the bottle.
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