This question comes up often, and it bears a look at the past with an eye on the future. Back in the day (say 1980’s) reasonably good specimens could be found for $75-$200. Many localities were in their heyday of producing (think Ojuela, Southern Illinois, Brazil, Tsumeb, Manganese Fields of Africa). New specimens were coming out at a frantic pace as commercial mining rode on a wave of high copper, lead, silver and zinc prices. The internet was relatively young, and only a few dealers had ventured this new means of selling minerals. It was either attend a mineral show or await a new video or catalog from a dealer you knew. Comparative pricing was not convenient or accessable.
Time passes as classic localities no longer produce
As the years wore on new developments in countries like China, Northern Africa, DRC, etc began to bear fruit. Miners learned of specimen values and how to properly extract them. Speculative specimen mining enterprises (think Sweethome or Rogerley) occasionally struck figurative gold with top quality highly desirable specimens. Prep labs learned new methodologies in trimming and repair.
In the meantime, classic tapped out localities (Iron mines of England or the silver mines in Peru and Germany) became more desirable and less available. Difficulty finding classic material in the market increased. The internet dealers grew from a handful to dozens to hundreds, making comparables somewhat easier but reliability a bit scarier. Newer finds slowed, as political unrest in countries like Afghanistan, Iran, DRC, etc made commercial mining nearly impossible. The costs of mining escalated past the feasibility of extraction as markets turned.
The early 2000’s and mineral specimen pricing
As we reached the turn of the century towards 2010 we saw the aging of the largest age sector- baby boomers. Boomers reached financial maturity, many of which were successful enough to have disposable income for collectibles. Fraud and escalating prices for art had those inclined ready for a new collecting challenge. The age of “investment” in mineral specimens was born. Dealers began differentiating themselves by the types of customers they wished to service. Many chose the high end, as the risk/reward proposition paid handsomely if the right customers were cultured. In the meantime trade shows , especially club shows, began to dwindle and the largest shows became more and more expensive.
Mineral show expenses become a greater factor in pricing
Booth fees range in the $2500 range for a 10X20 to well over $20,000 for a large booth at the major events. Staffing, pilferage, breakage, stands, lighting etc became more of an absorption factor. Domestic markets in foreign countries began to develop (think China), making the limited amount of good specimens more desirable, reducing expoting of good specimens.
Today, we find the consideration of what is “inexpensive”( under $200) and what is “expensive” ($25,000 and up) more divided than ever. The Mineralogical Records Tom Moore reports from Tucson yearly, and always looks for the HQLP category (high quality, low price). Low price, for Tom , is $100 or under. If you follow his writing each year that category becomes a greater challenge each year, and the specimens are usually small finds of more common minerals that are not very large.
That $50-$200 specimen from the 1980’s is now $500-$800 or more. Illinois fluorites that were so plentiful now only surface from recycled collections. Fluorites cleave rather easily and bruise even more easily. A top quality glassy surfaced deeply colored and zoned cabinet piece that may have sold at one time for $100 could now be $50,000. A Sweethome rhodochrosite you could have bought for $300 when they came out can be $75,000.
Playing the middle with pricing minerals
The middle market ($500-$10,000) consists of dealers who are either moving volume to make up for inadequate margin or that are constantly hunting for pieces that have escaped attention. Like antiquing, occasionally you find something someone else has not valued to market price. Where high end demands absolute perfection in aesthetics, lack of damage and provenance the middle allows for some variability in these factors. A third manner of maintaining a middle market position is to buy collections competitively (without taking advantage) and to keep a low enough overhead to use a markup that is satisfactory without trying to make each specimen a “homerun”. If a middle market dealer is too aggressive with pricing the higher end dealers will buy up much of their inventory , which then needs replacing (increasingly more difficult).
Thus, the pricing formula every dealer must consider is not just who they are selling to but how they are positioned in respect to other dealers with comparable material. Thet experience they wish to deliver to their customers becomes a top consideration. Some buyers put a great deal of value in a dealer that is prominent and highly respected. They will pay a premium for that feeling of security.
I hope this discussion provides some sense of the hows and whys of pricing. Value may be in the eyes of the beholder but that should be the mission for every dealer, to provide that value.