Can rubies contain inclusions?

Yes, natural rubies almost always come with inclusions, and they matter a lot for checking both the authenticity of the stone and where it actually formed. A natural ruby that looks fully flawless is extremely rare, and it feels pretty suspicious, because that often points to a synthetic, lab-grown version.

For example, common inclusions in rubies are microscopic rutile needles, which people call “silk”, plus liquid inclusions that can look like fingerprint patterns. Also, you might see small mineral bits such as calcite or zircon inside. Gemmologists use these internal signals to judge if a ruby was mined in Myanmar, Mozambique, or Madagascar. Now, when inclusions are heavy and threaten durability, or they cloud the gem strongly, the value tends to drop a lot. But fine silk that is spread evenly can help the colour by scattering light in a more balanced way through the ruby.