What is hallow gold?

"Hallow Gold" does not appear to be a commonly known term or concept. There is no specific information available about "Hallow Gold" as it may not be a widely recognized term or recognized within a specific context. It is possible that it may be a term used in a specific industry or field which is not well-known or may be a less common term for a specific product or material. Without additional context or information, it is difficult to provide specific details about "Hallow Gold".