These are 2 extracts from...

These are 2 extracts from https://www.geologyforinvestors.com/volcanogenic-massive-sulphide-vms-zinc-deposits/.

I have done the highlighting! - also the emoticons

VMS Size, Geometry & Distribution

The two features make VMS deposits such desirable exploration targets are their size and geometry. These deposits often form over a long time and can be reactivated on numerous occasions. This results in individual lenses that are a hundred meters thick and extend hundred meters along strike.  The reactivation also causes the deposits to be zoned around the black smoker pipe, with a predictable distribution of sulphides.

The massive accumulations of sulphides show up very well in geophysical surveys because they are both denser and more conductive than the surrounding rock, making VMS deposits relatively easy geophysical exploration targets.
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The shape of the deposits makes VMS ideal for cheap open-pit mining methods because a large amount of ore can be removed without having to remove very much waste rock. This is a much cheaper mining method than when ore is hosted in narrow veins, resulting in a much higher ratio of waste to ore removal..
VMS deposits often occur in clusters within a particularly small area (~10 km²) all related to the same event, since the metal-rich fluids may escape to the surface through many vents. The discovery of one large VMS deposit may well mean that there are other targets nearby.

Ore Minerals

The main ore minerals in VMS deposits are, unsurprisingly, sulphides, including pyrite (iron sulphide), sphalerite (zinc sulphide), chalcopyrite (copper-iron sulphide) and galena (lead sulphide).
VMS deposits contain minor amounts of silver and gold plus a large variety of other elements including cobalt, tin, selenium, manganese, arsenic, tellurium, antimony, and mercury among others. Some of these can be extracted as a by-product, increasing a mine's profitability