What's Right About the Exterior Restoration

One positive aspect of the exterior restoration is that the material being used is the proper material for repair work on Alamos' architectural heritage. It is slaked quicklime, bought from Calidra de Sonora in Hermosillo...about 85% pure. For fresco painting we usually look for 90% CaO or better, but the Hermosillo lime is probably sufficient for this work.

I question whether the lime used on the exterior has been slaked long enough. Generally one year of slaking is required before use.

Some suggestions were ignored by the restorers and the patron's group. A great opportunity was lost. The church project could have been used to raise public awareness about the uses of lime. Workshops could have been held to train local builders in how to use lime and how to prevent spalling.

Alamos would have enjoyed the long-term aesthetic and environmental benefits of decreased cement use, as well as increased protection of its cultural heritage.

Alamos used to produce what was reputed to be the best lime in the state of Sonora, but local production ceased years ago. Reinitiating local production might have an economic and environmental benefit for the town.