Book 37 Chapter 76 The methods of testing precious stones.
In Chapter 76 the methods of testing precious stones Pliny describes the methods in which one may test stones for their authenticity. Pliny describes some different ways to test stones such as, by color, roughness against surfaces, brilliancy, coolness, and weight. The first item chosen is obsidian stone which Pliny states the dust of can be used to test if a gem is disingenuine based on if it leaves a white mark when scratched by the obsidian. The next item is an illustration of the Ganges River in India. It is here that Pliny states is where precious stones come from. This chapter illustrates the necessity to test stones for their authenticity and offers the knowledge to do this.
Pliny offers knowledge as to how to test precious stones within this chapter. Pliny does this because falsifying commodities is a problem for the market of luxury goods due to the high price of the goods. Pliny offers the consumer a guide to test when purchasing these products. Pliny does not accept corruption in commerce and aids the consumers of these goods. It is my interpretation that Pliny believes including this information is necessary for a knowledge-based economy and so as the sale of false goods does not affect the market of the authentic goods. It is Pliny's goal to utilize knowledge of goods to ensure there is ethics in commerce (Gibson, 47-48).