When determining how to repair or replace stone, it is essential first to identify the existing stone’s physical and mineralogical properties. Identifying the type of stone and its condition can inform conservation efforts and assist in selecting an appropriate replacement. Therefore, this helps prevent potential damage to the surrounding masonry and allows for a better aesthetic match.
Stone Sampling & Preparation
Our in-house laboratory can receive stone samples by mail, or if local to the Southwest, a team member can visit on-site for a sample to be taken. When collecting samples, we always aim to use methods that cause as minimal disruption to the stonework as possible.
When collecting a sample yourself, ensure your sample is taken from an area that reflects your analysis requirements. For example, if you require the stone to be matched, ensure it’s from an area with little weathering, representing the colour and texture you want to achieve. Likewise, if you require identification of the cause of failure, ensure your sample comes from an area which has failed. A sample size of a minimum of 40x40x10mm is needed as a single piece.
Petrographic & Mineralogical Analysis
Our stone analysis includes a visual inspection and examination of the stone and its condition. Our team will use a thin section prepared from a sub-sample of stone for examination under a petrological microscope. This examination will identify the mineral composition and structure (type of stone), any flaws present and why the stone has failed. In addition, this analysis can identify the original source of the stone and often an appropriate replacement.
The stone analysis requires 5-8 weeks to prepare samples and complete the report.
Results & Report
Our team will provide the analysis in a detailed report that includes the results and any relevant interpretations and comments. All stone analyses are undertaken in our-house laboratory and follow international standards EN 12407:2019, EN 12440:2017, and EN 12670:2019.