Just to use as an example, how long it can take or for that matter---strange it may be; egg shell tincture is a great example of how long it can take.
Dr. John R. Christopher is about the only author I would trust that had history with making egg shells suitable as a human supplement.
In my case, the idea never thrilled me, but Christopher's history made it interesting to give it a try.
I started by wanting as natural chickens as possible, living in a free range area and you had to lock them up tight every night, because giant screech owls will kill ever chicken they can catch and for that matter, most large birds kill smaller birds--that is what they do. The you have minks, if a mink can find a tiny hole, it can jump, swim do what ever it takes and if it can get into a chicken house---1 mink will kill ever chicken before day light. Not to mention dogs, most dogs hates chickens and in nature, just about everything that eats meat, hates chickens and wants them dead and in their bellies. A coyote or fox will send years eating your chickens, until the last chicken is dead---then they will leave and not before.
So my goal was as natural as possible, eating worms, bugs, fruits, berries, etc. They will eat most any vegetable or fruit and it is VERY HARD to raise a chicken that does not eat meat and suck blood------you must give them all the worms and bugs they can find and even then---if 1 chicken starts to bleed 1 drop of blood---all the chickens wil jump on that chicken and turn it to bones before you knew what happened---this is why amish feed chickens dead animals, especially dead chickens and why no one should ever want to eat an Amish raise egg or chicken.
All that said, within about 3 years, I collected 100 dozen egg shells---because it is near impossible to shell chicken eggs and if you do, people will only give you 1/2 what the feed cost you yo keep the chicken alive-----you loose $$$ on any farm product you can imagine--if you try to raise it correctly. People are addicted to cheap, subsidized factory farm products and they only care bout the price and nothing more as a general rule.
so once I had 100 dozen chicken egg shells, I gave the chickens to the neighbor down the road and I assume he eventually ate them all, or predators ate them all..
The internet will have people eat chicken shells by various means...i would never suggest that.
Dr. Christopher used raw apple cider vinegar to slowly dissolve the egg shells. So I purchased amish made apple cider vinegar and soon learned you really should make your own--so I did that and used many fruits and not just apple, but apple is by far the dominate fruit.
100 dozen egg shells is allot, even if you smash them all up.
So I did what Christopher said and then added a little fresh apple cider every few years and blended it all up again and again and this is the 10th year they have soaked in raw vinegar-----the vinegar enjoys eating the egg shells and makes a really thick "mother" jelly seal about 1+ inches thick. Some people eat that thing and I suggest no one should ever try that.
Long story short, after 10 years, I ended up with a final product of 14 gallons as a proper made tincture. As a proper made tincture, which is water free, it will literally last hundreds, if not thousands of years if you keep the glass sealed.
14 gallons is probably 14 x lifetime supply.
I doubt I ever try it as a stand alone tincture---the idea of chicken eggs will never appeal to me--but within a calcium bone building rich formula--that I can handle. the final tincture is as sterile as sterile gets, but just the idea that the egg came from a chicken's butt, is just not appealing, that and the fact, this is not an herbal product, other than the vinegar used to extract the minerals from the eggs.
CHICKENS have very powerful acids, they can dissolve minerals from rocks that humans never could. Dogs and many meat eating predators all can, especially the birds.
In the dog world, i have seen miraculous healing such as a old dog that dragged both rear legs for a full year and after being fed none natural rock like substances----not only did their legs return, the dog could run another full year behind horses.....the dog was never dewormed or much of anything else---that was 20 years ago..... Dr. Hans Neiper around 1970 discovered how elderly old bed ridden women could grow brand new hips--using cow bone supplement (injected). IN BOTH theories the BLOOD did all the work after they the blood was fed the raw materials.
Dr. John R. Christopher bragged he had a box full of dentures from patients that grew a third set of teeth--------yet I have never seen that box of dentures--if it existed, you would have believed they would still be showing it off even today---but they do not. Pastor Hotema has some third set of teeth stories, but they resulted from the opposite theory os ALKALINE, while using bones/eggs uses an acid approach (vinegar).
There are more than a handful of herbs with a history of dental health....from China to USA, there are calcium rich herbs with long history of building new bones and teeth---the chicken eggs are the strangest and by far took me the longest to finish.....
YES, it would be easier to just eat egg shells like the bozo's on utube instruct, but what fun would that be.