I chose "quartz" as a medium difficulty word for Hangman. At 6 letters, it fits within the required length. It contains uncommon letters like 'q' and 'z', making it challenging but not impossible. It's a real English word referring to a common mineral, not a proper noun or acronym. The word has no repetitive letters, which adds to the challenge while keeping it fair. The player will likely guess common vowels first, revealing 'a' and 'u', but may struggle with the consonants, especially 'q' and 'z'.