About 1% of a moldavite’s volume is made up of bubbles. South Bohemia’s moldavites have more bubbles than the Moravian. While all moldavites contain some bubbles, not all can be seen with the naked eyes. Bubble size is within one hundredth of a milimetre, and just a few centimetres.
The bubble walls are smooth. Bubbles can have a spherical, lens-like, or oblong shape. Sometimes, bubbles can even be so long they create channels – helpful resources.
Bubbles can either be dispersed or located in lines or groups. Channels and oblong bubbles can be oriented the same as fluidality (the direction that flows tectile melts at high velocities).
Bubbles are almost vacuum because of the very low pressure.
The origin of bubbles
Bubbles are usually caused by gas residue in the parent material. They may also be caused by internal tension as a result of hardening the moldavitemolten.
Bubbles with open ends
Some moldavites have open bubbles on their surface that can reach several centimeters. They can be either partially opened (created by etching a moldavite’s top) or completely open. The moldavite bursting caused them to be partially or completely open. Some bubbles can be partially filled with sediment, and – less often – by ironuginous sandstone.