I live in Australia. We have had these bottles for many years but cannot remember where we found them. Possible from a shipwreck in Spice Islands of Indonesia, or Australia where we live. Any help with dating or information would be appreciated.
Appears to be black in color but has creamy yellow hard growth all over. Cannot see a seam vertically may be hidden by coating, but definitely one going across the bottle below the neck. The necks are distorted in shape, in one I can clearly see random lines in the glass. There is definitely a small pontil mark on the base of one. The mouth of the bottles are very unusual and crudely made.