What is the oldest Prime flavor?

Could you please clarify what you mean by "Prime flavor"? Are you referring to a specific type of cryptocurrency, a financial instrument, or perhaps a product within the cryptocurrency or finance industry? If we're speaking in the context of cryptocurrencies, it's worth noting that the term "Prime flavor" isn't a widely recognized term in the industry. However, if we're assuming you're asking about the oldest prominent or popular cryptocurrency, Bitcoin would likely be the answer. Bitcoin was the first decentralized digital currency, created in 2009 by an individual or group of individuals under the pseudonym Satoshi Nakamoto. Since its inception, Bitcoin has become the most well-known and widely used cryptocurrency, with many other cryptocurrencies following in its footsteps. But again, please let me know if I've misunderstood your question or if you're referring to something else entirely.