If you are looking for the download right now, I cannot provide a direct unauthorized download link, but I can direct you to the legitimate sources:
Have you used Gradistat v9.1? Let me know in the comments if you prefer the Method of Moments or Folk & Ward parameters for your specific environment!
is a widely used Microsoft Excel-based program designed for the rapid analysis of grain size statistics from unconsolidated sediments. It was originally developed by Simon J. Blott and Kenneth Pye. Core Functionality
The software automates the calculation of essential sedimentological parameters from raw data obtained through techniques like sieving or laser granulometry: Statistical Measures
: It calculates mean, mode, sorting (standard deviation), skewness, and kurtosis. Calculation Methods : Statistics are computed using both the Method of Moments (arithmetic and geometric) and the Folk and Ward (1957) graphical methods. Data Scales
: Supports results in both metric (micrometers/millimeters) and logarithmic (phi) units. Graphical Outputs
: Generates frequency plots, cumulative distribution curves, and ternary diagrams for sediment classification. Versions & Compatibility Version 8.0
: Released in 2010, this version was optimized for Microsoft Excel up to the 2010 version. Version 9.1
: While "v9.1" is often cited in academic datasets and research papers for grain size analysis, official legacy downloads typically point back to the Kenneth Pye Associates Ltd (KPAL) software page GRADISTAT-PRO
: A fully revised version with expanded functionality has been noted as under development by the original authors. Alternative Tools
Due to compatibility challenges with newer versions of Excel, some researchers utilize the
package in R, which was built as an evolution of the GRADISTAT macro. It provides similar descriptive statistics and can be accessed via a web-based interface for those unfamiliar with R coding. Official Links Software Homepage KPAL Gradistat Academic Reference Blott and Pye (2001) Paper into the Excel macro?
GRADISTAT Version 9.1: The Definitive Guide to Particle Size Analysis Link and Utility
Particle size analysis is a cornerstone of sedimentology, engineering, and environmental science. Since its inception, GRADISTAT has remained the gold standard for researchers seeking to transform raw sieve or laser diffraction data into meaningful statistical insights. With the release of Version 9.1, the software continues to streamline the calculation of grain size statistics using the most recognized methodologies in the field. What is GRADISTAT v9.1?
Developed originally by Simon Blott, GRADISTAT is a Microsoft Excel-based program designed to analyze grain size statistics. It automates the complex mathematical processes required to understand sediment distribution. Version 9.1 represents a refined iteration of this tool, offering compatibility with modern spreadsheet environments while maintaining the rigorous analytical standards required for peer-reviewed research. Key Features of GRADISTAT v9.1
The software provides a comprehensive suite of outputs based on a single input of weight or volume percentages. Key features include:
Folk and Ward Method: Calculations for mean, sorting (standard deviation), skewness, and kurtosis.
Method of Moments: Arithmetic, geometric, and logarithmic statistics.
Physical Descriptions: Automatic naming of sediment types (e.g., "Very Fine Sand").
Distribution Curves: Generation of cumulative and frequency distribution graphs.
Sieve and Laser Data Support: Compatibility with various data collection methods. Accessing the GRADISTAT v9.1 Link
Finding a reliable link for GRADISTAT v9.1 is essential for academic integrity and software safety. The program is typically distributed through university repositories and research gateways. Official Research Gateways
The most secure way to download Version 9.1 is through the author’s official distribution channels or academic hosting sites:
ResearchGate: Dr. Simon Blott frequently updates his profile with the latest versions and manuals. Search for "Simon Blott GRADISTAT" to find the project page.
University of Hull: Many users find the software hosted through UK university sedimentology departments where the tool was originally developed and refined.
KSU Sedimentology: Kansas State University and other geosciences departments often maintain mirrors of the .xls file for student use. How to Use GRADISTAT v9.1
Using the software is straightforward, provided your data is formatted correctly.
Prepare Your Data: Ensure you have your sieve sizes (in microns or phi) and the corresponding weights or percentages.
Enable Macros: Since GRADISTAT runs on Excel VBA, you must "Enable Content" or "Enable Macros" when opening the file. Input: Paste your data into the designated "Input" sheet.
Run Analysis: Click the "Calculate" button provided within the spreadsheet interface.
Review Results: Navigate through the tabs to view the "Summary," "Statistics," and "Graphs" sheets. Why Version 9.1 Matters
In grain size analysis, consistency is vital. Version 9.1 ensures that your data is processed using the latest bug fixes and compatibility updates for Excel 365 and Windows 10/11. This prevents the "Runtime Errors" often found in older versions like v4.0 or v8.0 when handled by modern operating systems. Conclusion
GRADISTAT v9.1 remains an indispensable tool for anyone working with physical geography or sedimentary geology. By using the links provided through academic repositories, you can ensure your data is processed accurately, efficiently, and in accordance with global scientific standards.
Is it legal to use the gradistat v 91 link? Since v 9.1 was released as Freeware (not trialware), the original license permitted free distribution for academic and non-commercial purposes. However, because CCAP no longer supports it, using v 9.1 is generally considered "legacy use." You cannot use Gradistat v 9.1 for commercial consulting without purchasing the Pro version.
The search for the gradistat v 91 link highlights a larger issue in geoscience: the fragility of academic software. Unlike commercial apps, niche scientific tools often disappear when hosting fees lapse or developers retire.
Today, the scientific community is moving toward open-source reproducibility. We are seeing the emergence of R packages (G2Sd) and Python scripts that replicate Gradistat’s statistics exactly. However, for the non-programmer, the Excel-based Gradistat v 9.1 remains the gold standard.
Official Source: The software is freeware but requires permission from the author for commercial use. It is hosted on the Kenneth Pye Associates Ltd website.
Important Note on "v 91": The standard public versions are usually labeled v8 or v9. If you have a file specifically labeled "v 91," it is likely a specific university modification or a typo for v9.1. Always scan downloaded Excel macros with antivirus software before enabling macros.
If you are importing data from a Laser Particle Sizer (like a Malvern Mastersizer):
