I believe GDX will make a run up to at least $38.41, and potentially higher.
The measured move is confirmed by long hand as well as Fib. extension:
1. High of $33.34 minus it's low of $21.52 (Point A) = $11.82. Point B's (retracement) low of $26.59 + $11.82 = $38.41. 2. Drawing the Fib. extension as show on the chart confirms the same price target.