Occluded Gas

Occluded Gas
Gas trapped when the silver ingot was cast could have remained when the strips were rolled out.If the trapped gas was near the planchet surface,then it may result in RAISED BUBBLES on the struck coin. However,occluded raised bubbles are very rare on morgan dollars.Raised bubbles can also be seen on coins that have been heated or been in a fire,but that is usually obvious with dark areas or deformed ares on the coin.~Wonders of Morgan Dollars by LVA
Leroy has determined that the Bubble seen in the picture below is not actually denticle impressions, or gouges, but occluded gas bubbles.