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Since the 1940s, when maritime archaeology was established, the systematic excavation of submerged wrecks began to be refined. Systematic excavations led to the recovery of a vast array of organic and inorganic artefacts, including human and non-human bones and teeth. In order to preserve the materials recovered from the sea, the discipline of maritime conservation rapidly expanded and dealt with unique issues, including, but not limited to, marine salts’ encrustation of archaeological artefacts. Bone and teeth are organic artefacts which provide crucial information about natural and social environments of the past. When recovered from marine settings, they are often friable and require conservation processes and consolidation treatments, e.g., to prevent shrinkage during drying. However, conservation processes and consolidants can interfere with pathological, traumatic and taphonomical evidence associated with bone and teeth, and can bias sample preparation and analysis through mechanical action and chemical composition. The aim of this paper, in which a few examples of interference are listed, is to highlight the need of accurately documenting any type of conservation process and/or consolidation treatment that has been performed on bone and teeth stored in archaeological collections. This becomes essential when samples are selected for study, especially if this includes destructive analysis, and will assist in clarifying any conflicting results, leading to reliable interpretations.

Currently the application of consolidants based on nanoparticles is common practice among restorers. Consolidants should not modify the properties of original materials according to international recommendation, which requires previous studies to decide the optimal option. The selection must be based on empirical results, and not only in the expertise of the restorer, because the consolidant’s effectiveness is influenced by its own properties and other factors such as the characteristics of the artwork (elemental composition, porosity, texture, etc.) and its context (temperature, relative humidity, etc.). Moreover, new protocols must be sustainable and compatible with on-site restoration. A new protocol to test consolidant nanoparticles has been designed and assessed. This is based on easy trials and low-cost techniques—digital microscope, colorimeter, peeling test and ultrasound—that could be employed by restorers in situ. In this paper, different consolidant nanoparticles were tested on stones from two historical quarries. The first treatment was SiO2 nanoparticles, and the second, a new nanocomposite of Ca(OH)2 and ZnO quantum dots that allows us to measure penetration depth easily and discern the treated areas under UV lights. This second treatment was the best option for the studied stones, validating the protocol designed for the choice of consolidants.