How to tell if kava is good quality?

Could you please elaborate on the key indicators for identifying the good quality of Kava? I'm particularly interested in understanding the visual cues, such as color and texture, as well as any sensory tests that one can conduct to determine freshness. Additionally, is there a particular smell or aroma that should be present in high-quality Kava? Moreover, how does the source of Kava, whether it's wild-grown or cultivated, affect its quality? Lastly, are there any specific certifications or labels that I should look for to ensure I'm getting the best possible quality? Your insights would be greatly appreciated.