Early members broke good china so that the stucco of the Kirtland Temple would sparkle

Unlikely

There is no contemporary account of members breaking their china and adding it to the stucco of the Kirtland Temple so it would sparkle. In fact, it would have been foolish to break the china because it could have been sold for much needed funds. The old stucco was replaced in the 1950’s and modern analysis was also not able to confirm this early story of sacrifice.

The original exterior stucco did contain glass and sparkled in the sun. Whether or not any china was used is not clear, since the recipe of the stucco was never released. By family tradition, the stucco most likely included hair, glass and china. There was a glass company in the area and it is most likely that the majority of the glass used was waste glass or old bottles. Reports of fine china being donated and broken have not been able to be verified over the years.

Many people have submitted quotes from church leaders, including President Hinckley, that mention the broken china. The broken china story can also be found in many church publications, including lesson manuals. Although it is plausible that china was used, it is most likely that this was already broken china and not good, usable china. And the fact remains that no documented account of breaking good china to be used in the stucco exists. Because of this, the myth will remain classified “unlikely”.

Craig K. Manscill, associate professor of Church History and Doctrine at BYU wrote the following in “Artemus Millet: Builder of the Kingdom“:

Much has been said concerning the exterior stucco of the Kirtland Temple. The common story is that the women of Kirtland donated their fine china to be crushed and mixed in with the stucco, thereby adding a shimmering surface. That glass was put into the plaster is true, yet there are no records that tell of any fine china. Artemus’s journal and other contemporary accounts use the phrase “old glass and crockery.” His son recalled, “Artemus sent men and boys to the different towns and places to gather old crockery and glass to put in the cement.” Stories about fine china being mixed in the Kirtland Temple stucco do not appear on the historical record until 1940—over a hundred years after the dedication of the temple.(Pg. 64)

Check out this LDS Living article for another viewpoint.