# How long do the resources last in a Starcraft 2 base?

In a standard SC2 league map, how long do the mineral patches and vespene geysers last? I know that you should start expanding before the resources start to dry up, and so I’m curious what the time frame is.

I’m curious how long they last at your starting base (assuming you continuously produce workers until you have 30 to saturate collection), and how long they last in an expansion site, where you start by sending about 10 workers there, and then build more until 30ish.

Using the numbers tzenes gave:

• Start out with 8 mineral patches, each with 1500 minerals
• An SCV takes 22 seconds to build
• The first 2 SCVs on a mineral patch will gather 45 minerals a minute each, while the last one can be considered to gather about 12

In other words, there are 12,000 total minerals to gather; the first 16 SCVs will gather 45/min, the last 8 will gather 12/min. Using this knowledge (and not taking MULEs into consideration!), we can construct a table:

``` Seconds  | Number   |  Resource gather rate  |   Total minerals
elapsed  | of SCVS  |  (minerals / minute)   |  gathered (approx)
------------------------------------------------------------------
0 |     6    |          270           |        0
22 |     7    |          315           |       99
44 |     8    |          360           |      214.5
66 |     9    |          405           |      346.5
... |   ...    |          ...           |      ...
198 |    15    |          675           |     1485
220 |    16    |          720           |     1732.5
242 |    17    |          732           |     1996.5
... |   ...    |          ...           |      ...
374 |    23    |          804           |     3672.9
396 |    24    |          816           |     3967.7
```

So at the time your 24th SCV is built and you become fully saturated, you could have mined about 3968 minerals. The remaining 8032 will then be mined in about 590 seconds, giving an overall time of 986 seconds, or about 16 and a half minutes.

Of course, this is a lower bound. In a real game, the actual time will be slightly longer because:

• Some SCVs will be building/scouting
• Some SCVs will be mining gas instead
• Not all mineral patches will deplete at the same time, so your resource gather rate will actually go down near the end. Hopefully by this point, you have several other expansions 🙂