OVERVIEW
The largest map in the game, Zircon has plenty of free real estate. The sheer size boosts the viability of lategame econ builds. But make no mistake- just because games are typically longer, doesn't make the map slow! Aggressive earlygames have taken several surprise victories on this map.
As long as no serious mistakes are made by either player, this is the longest map in the game, with some games taking as long as 60-90 minutes to complete.
STRATEGY
The Rich Resources on this map promote the spirit of sharing :) Each player can grab their corner of both rich patches, making Gold-heavy builds commonplace. Centralized (or alternatively lane-focused) Barracks placement is paramount in pressuring and defending the Mines as well.
Combat on this map is much less about microinteractions and more about large-scale guessing where the opponent's troops will be. Think they're getting greedy on a resource patch? Setup a Barracks right outside. Are they neglecting a lane entirely? Knock on the Fort's door with some Horseman!
BUILDS
P1) T1 2 Mine | T2 Mine | T3 Builder | T4 2 Barracks or Barracks Mine
P2) T1 2 Mine Scout | T2 Mine | T3 Builder | T4 2 Barracks or Barracks Mine
The map standard (and my favorite) build, this takes advantage of that the lone Builder can reach the near Rich Resources and build a Mine on them by Turn 2! This emphasizes the buildiness of the map, setting up a greedy +120/Turn by Turn 4. If done right, you should end up with 2 builders in each lane, and your choice of placement of 2 Barracks.
That's the only build this week! Others are likely possible. This map could use more experimentation.
SUMMARY
Like building? Setting up grand Armies for large scale battles? This is the map for you!
Want to jump straight into combat, and don't have very much time? You should probably avoid this one.
As the biggest and oldest map, Zircon emphasizes the "large" in "large-scale tactics".