The Monument commemorates the miners who lost their lives in the quarries while extracting diatomaceous earth (fossil shell flour), the industrial processing of which began in the Amiata region in 1913. The Castel del Piano deposits are considered to be among the best in the world since they originated from deposits of diatoms formed in fresh water. The deposits are the result of the rapid and constant stratification of algae. On completion of their life cycle, the algae sank to the bottom of the ponds where they accumulated in strata of diatomaceous earth measuring ⅘ meters thick. Targeted drilling was carried out on these strata which brought soil samples to the surface. The extraction work was generally carried out in the open air and, due to limited space in the quarries, the material was transported in wheelbarrows pushed by hand before being sent to be processed on wagons that moved on rails. The chemical purification process took place in calcification and refining ovens by mixing the extracted fossil shell flour with salt and subjecting the mixture to a very high temperature.
The monument was inaugurated during the Festival of Tuscany on 20th October 2015. The artist Cristina Pellegrini, who graduated from the Academy of Fine Arts in Florence, was commissioned to study the design and present a series of sketches which are still preserved in the Municipality building. Among those chosen was "The man with the chisel on his knees", a man with a mallet in his hand engrossed in working a block of stone. The work was then sculpted in low relief and donated to the Municipality of Castel del Piano by the sculptor Umberto Dondolini, one of the last remaining stonemasons in the Amiata region. Born in 1939, Dondolini also made two other sculptures which are situated on Via di Montegiovi and in Piazza Donatori Diangue respectively. The first depicts the transformation of a drinking trough for animals into a fountain (2018), and the second is a tribute to the presence of the historic Avis Association which was founded 60 years ago. During his career, Dondolini also worked for the Superintendence of Fine Arts in Florence and on prestigious construction sites such as the Sant’Antimo Abbey and Forte Stella at Argentario.