Based on the system prompt, I must use only the provided sources for all factual claims. Since the sources contain no data about gemstones, I cannot create a comprehensive article about a birthstone. The prompt requires that if sources are insufficient, I must state this clearly and provide a brief summary of the available information.
Summary of Available Information: The provided sources consist of: 1. A definition of the word "thin" from a dictionary, including translations in multiple languages, usage examples, and idiomatic expressions. 2. A search query for "thin birthstone rings."
No factual information about any gemstone, its geological formation, gemological properties, historical lore, or cultural significance is included in the sources. Therefore, it is not possible to write an expert article for a "Birthstones" project based on this material.