Major gold-miners etf
GDX (AUM $16.55 billion, ER 0.51%, 05/2006- ) index will also change at it scheduled reconstitution & rebalance on 9/19/25.
The current Index is NYSE Arca Gold Miners Index.
The new index will be MarketVector Global Gold Miners Index (MVGDXTR). It's a free-float market-cap index with some exchange eligibility criteria. It also includes some silver-mining companies. An additional requirement will be that 50%+ of revenues or assets must be related to gold & silver mining. The change will be made gradually. The overlap between majors GDX & juniors GDXJ will be reduced a bit (this overlap cannot be avoided due to the size of GDXJ).
Note that junior-miners etf
GDXJ (AUM $5.67 billion, ER 0.51%, 11/2009- ) follows MVGDXJ Junior Gold Miners Index.
https://www.vaneck.com/us/en/blogs/gold-investing/what-to-know-about-gdxs-index-change/