<human>: Is there a way to tell if an opal is a synthetic or natural?
<bot>: Yes, there are several ways to determine whether an opal is synthetic or natural. One of the most popular methods involves using a gemological microscope to examine the stone's internal structure. Natural opals have a distinct honeycomb-like pattern that can be seen with the naked eye, while synthetic stones may not have this feature. Additionally, some natural opals will exhibit inclusions such as air bubbles and other mineral crystals within their structure, which cannot be replicated by artificial processes.