What's a Wilber?

Mineral Matters #287

This photo came up as a Facebook memory from 2018.

My description of it was:

Acquired this Tsumeb wulfenite yesterday. Tiniest little “Wilbers” on the corners of the main crystal but these don’t detract except under magnification. On the plus side, there are at least 39 perfect micro wulfenites on the specimen. Plenty of scope for good photos.

So where did the term “Wilbers” come from?

Well, it was a phrase used to define the tiniest damage to crystals, particularly crystal edges, and called “Wilbers” after world-class mineral collector, Dave Wilber. He used to look at a specimen with his 10X, find a ding, and comment on it.

Update: Quintin Wight let me know that Paul Desautels had a definition list that said “Two Wilbers make a Ding, two Dings make a Chip—and so on”. 

Is a “Wilber” a bad thing? Well that depends on how “perfect” you want your mineral specimen to be. Realistically, some degree of compromise is usually going to be required. Most specimens will have some form of distraction, and the more magnification you use, the more likely you are to see it! The curse of a super macro photographer! 😣

Below: Wulfenite, Tsumeb, Namibia.

Below: Dave Wilber, Tucson 2012.