The metal is expensive, not because it is rare but because of the expense to produce and work it. The minerals mined for titanium are all oxides, unlike many base metals that are mostly mined as sulfide minerals.

With successively lower temperatures as the water mixture cools, new sets of minerals are formed and many of those stable at a higher degree of heat became subject to alteration as the temperature progressively moved lower.

When we got set up and I started to swing the coil over a small mound, I got a good signal, faint but repeatable.

My friend came walking in from the garage with what looked to me like a stick of dynamite. Chuckling, he said, “Have you ever been gold mining?”
In my head I was thinking, “Not at 3 am in the morning with dynamite.”