Moonlight Mahjong 2.2.1 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. The software is included in Games. This free software for Mac OS X is a product of Midnightmartian.
From the developer:
Moonlight Mahjong is the popular 3D Mahjong Solitaire game created for the iPhone and iPad... now for OS X! Play arcade-style with progressively difficult levels, or relax with one of the non-competitive game modes. The gameplay is simple yet addictive.
Originally created for touch-screen iOS devices, Moonlight Mahjong on the Mac takes full advantage of a multitouch trackpad, but also can be played with a mouse.
You may want to check out more software for Mac, such as Moonlight, Mahjong Unlimited Free or Astraware Mahjong, which might be similar to Moonlight Mahjong.