I don't mean to be argumentative, but I would like to respectfully disagree with the above two posts. Any bottle hunter (and I haven't dug bottles in 30 years, so I have no personal dog in this fight) can tell you about or show you the damage that being in the ground does to bottles.
Most of the broken bottles found in old dumps were whole when put there. Freezing temperatures will crack glass. Tree roots grow into them and break them. Iron and other mineral deposits destroy the finish, and the embossing on the bottles gets scraped and worn by the dirt, as do any decals and transfer designs. Bottle lovers go through a lot of work and expense in trying to bring them back to their original beauty.
And as for estate agents throwing the old ones in the trash: doesn't happen. A deceased bottle enthusiast's collection will go to an auction or show, to be resold to collectors who will further preserve them.
Most of the broken bottles found in old dumps were whole when put there. Freezing temperatures will crack glass. Tree roots grow into them and break them. Iron and other mineral deposits destroy the finish, and the embossing on the bottles gets scraped and worn by the dirt, as do any decals and transfer designs. Bottle lovers go through a lot of work and expense in trying to bring them back to their original beauty.
And as for estate agents throwing the old ones in the trash: doesn't happen. A deceased bottle enthusiast's collection will go to an auction or show, to be resold to collectors who will further preserve them.