Numerous factors can contribute to cause the breakage of a gravestone, monument, or sculpture. The press loves to focus on the deplorable acts of vandalism, which from time to time, may damage a local cemetery or graveyard. Yet these occasional rampages are not the leading cause of broken gravestones.
It is next to impossible to protect an open air museum, such as a burying ground, from all the potential causes of degradation. Yet, proper maintenance will go a long way towards helping preserve are heritage carved in stone.
I have seen too many tree limbs fall and shatter fragile marble gravestones into unrepairable fragments, tree which were dead and should have long ago been pruned. I have seen cars crash through fences and destroy gravestones and monuments, toppling them like so many dominos. I have seen heavy lawn mowers mercilessly chip away and gash historic tombstones repeatedly, until they finally snap where they meet the earth. I have seen monuments crash into open graves, and get run over by trucks.
Many techniques have historically been employed to join fractured tombstone together. Although the drilling and placement of bolts and metal repair plates is no longer advised, for many years this was considered a well done repair. Mortars were traditionally employed to join broken stone fragments, but mortars tend to be too thick and cause mating surfaces to be enlarged. This in turn makes multiple fragments joining difficult and often unattractive in appearance.
We should be very careful to avoid disparaging preservation procedures completed in a different era. If these earlier attempts towards conservation are still intact, at least part of their objective has been achieved. They may not always look that great, but consider if a repair was not completed at all, the fragments may have been lost or destroyed completely.
Mending Broken Stone
Many things can cause the breakage of a gravestone, the question at hand, is can it be repaired? Luckily, modern epoxies have evolved in the recent past, which now allow gravestone conservation procedures previously impossible, to be accomplished.
Provided to stone itself still has enough of its structural integrity intact, the fragments can usually be joined back together, or be conserved, (repaired). Although joining two or more broken elements is a seemingly basic task, it can quickly become complex. The type of stone to be conserved, and where it is broken, both need to be assessed before a preservation effort may begin.
Broken at Ground Level
The most common type of tablet gravestone breakage, tends to occur, at the point which the stone enters the ground. Many forces combine at this grade level, to place excessive stresses in the stone. If the gravestone has begun to tilt, toward its front or back, constant pressure is exerted here, with the weight of the stone acting like a lever. The taller the stone, the greater the forces will be, the thinner the stone, the more likely it will snap.
A good method to conserve a gravestone broken near the ground level is explained in the AGS web site. A new replacement base is cast with a socket, and the gravestone is then set in place, with a high lime mortar. There are problems with this method, as uneven breaks on the stone must be trimmed away. Also the underground portion of the stone must be removed if it is to be reset in the same location.
Historically many tombstones were repaired by puddling them into concrete. This mean a hole was dug, concrete placed in the hole, and the tablet stone fragment was stuck into a puddle of concrete. This technique is not advised as it will make future preservation efforts difficult or impossible.
Another method is to simply reset the gravestone in a lowered position. This may be the quickest method, and may be reasonable temporary measure. In order to safely reset a monolithic stone, at least one third must be buried under ground. In order to achieve this objective, inscription may have to be placed beneath the ground.
Stone Epoxy Mends
Wear gloves when working with all epoxies. All fragments to be joined, must be thoroughly cleaned and dried before any epoxy can be applied to the mating surfaces. Be very careful to apply epoxy to one of the mating surfaces only, without spreading it too close to the edge. When the fragments are joined, this will help avoid any squeeze out from occurring. Excess epoxy can be removed with a solvent before it hardens, but this can also weaken the joint if it is penetrates into it.
The biggest causes of epoxy repair failures may be avoided by following a few guidelines.
- Make sure the stone is dry. A propane torch may be used to quickly evaporate moisture in cooler weather. Pass the torch back and forth quickly, as not to really heat up one spot. Most stones will lighten in color as they dry, so this is a good indicator.
- If the stone is too cold the epoxy will not cure properly. It may be wise to let the sun warm up a stone on cooler weather.
- If rain or cold weather is due to arrive, it may be wise to wait until a nicer day to complete an epoxy repair. The majority of stone epoxy repair failures are caused by cold, moisture, or poor surface preparation.