Preservation is a means of preventing damage due to age, handling, or outside elements. Conservation is a means of restoring an artifact to its original condition. Because gravestones are historical artifacts, any conservation or preservation should, ideally, be done by a professional conservator. However, simple repairs can safely be done by volunteers and non-professionals if a few simple rules are followed. Here are the primary things to know before you attempt any kind of work.

• Gravestones are irreplaceable primary source documents. Thus, the less tampering you do to them the better. Protect the original historic value and integrity of the stone by altering it as little as possible.
• Gravestones of the 17th, 18th and 19th centuries are extremely delicate. Damage is easy to do, difficult to undo.
• Inappropriate conservation techniques, such as the use of bleach to clean a stone, weaken the stone and shorten its lifespan. This damage is not always immediately apparent.
• In terms of preservation and conservation, it is better to do nothing than to do the wrong thing.
• Before beginning any restoration or conservation project, take time to research the project. This will ensure that the project is completed in a manner best suited to both the stones and the site itself.
• Any repairs must be done using reversible techniques. This will allow us to take advantage of better techniques as they are developed in the future.

One of the most commonly asked questions is where to begin a restoration or conservation project. A good way to start is by documenting the site. However, regardless of where you begin, research is an important first step. When documenting the site, first determine if any prior documentation has been done. If so, these records may have been deposited at the local library, historical society or town hall. There may also be a copy at the New Hampshire Historical Society, the New Hampshire State Library or the New Hampshire State Archives. It would be unfortunate to duplicate work that has already been done. However, all prior transcriptions should be verified for accuracy and completeness.

Before beginning any restoration, preservation or maintenance, several questions must be asked. First, has any attempt been made to locate descendants who can authorize the work? If no relatives can be found, you must check with the selectman or cemetery trustees for any ordinances related to your local graveyards. Some towns claim jurisdiction over all burial grounds, both public and private.

Another important consideration is the issue of continued maintenance of the site. Will volunteers be able to sustain this work, or can funds be voted by the town? Is there a possibility of trust funding from a relative?

Prior to beginning the work, it is also important to notify the local police so they will not consider your work vandalism. The nearest neighbors also need to be informed, or they will call the police. Newspaper publicity can aid in explaining your project to the community. Whether the work is done by an individual, or as a community project, it is critical to work with the community and within the law.

We stress the importance of research on the best methods to restore old graveyards and the stones they contain. Though non-professionals can do good work, it's critical to understand and use best practices. Poor restoration methods can be extremely detrimental to the life of the stone.

Finally, some towns or individuals may elect to consult with or hire a professional conservator regarding gravestone repair. Identifying a reputable and knowledgeable professional can be a challenge. Good guidelines for this can be found in A Graveyard Preservation Primer by Lynette Strangstad. In New Hampshire, one may also contact the Division of Historical Resources for advice (see Section V for their contact information).

Documenting a graveyard is one of the most important ways to preserve the information contained there. This is best done using inventory forms and photographs. Using standardized forms ensures that the information gathered is accurate and complete. One of the biggest problems we've experienced is that many of the graveyard inventory projects previously done are missing vital information such as epitaphs, type of stone, and location. We have also worked with many records that were alphabetized by surname rather than by burial location. This makes it difficult for researchers to locate the gravesite. In addition, this may obscure the relationship between family members with different surnames. To avoid this problem in the future, The New Hampshire Old Graveyard Association has developed two forms to aid in the gathering of information.

Before beginning any type of cleaning or repair, it is important to know what not to do and why. Here are some of the techniques to avoid. Proper techniques will be addressed as well.

Sand Blasting and High Pressure Water Washing. Neither of these methods should ever be used. They remove a surface layer of the stone itself, a form of mechanical erosion.

Bleach. Using bleach to clean discolored marble stones is a temptation to many people. However, it's one of the most detrimental cleaning techniques that can be used. Bleach causes invisible, irreparable damage by eating away at the surface of the stone and exposing a softer at-risk under layer. The exposure of this under layer to the elements causes the monument to decay much more rapidly than it would normally. Bleach also leaves a residue behind that no amount of rinsing can remove. Other commercial cleaners such as Ivory soap and Fantastic pose the same danger. This is because calcium ions in the stone cause the cleaning agent to become insoluble in water. Chlorides are inevitably left behind and these cause migrating salts to form beneath the surface of the stone. As the crystals grow and exert pressure from below, they cause the surface of the stone to slough off. Other harmful cleaners include muriatic acid, phosphoric acid (such as Naval Jelly and Lime Away), alkaline cleaners and corrosive biocidal cleaning materials.

Recommended Techniques.

The best way to clean a gravestone is to begin with the least damaging product. Start with plain water and a soft brush. Patience and perseverance are the keys to this technique. Remember that whenever two objects (such as the brush and the stone) are rubbing against each other, some abrasion occurs. To minimize this, scrub as gently as possible. Scrubbing from the bottom up prevents streaks. If water alone does not work, conservator's supply houses sell non-ionic detergents that are safe to use on granite, marble, limestone, sandstone and slate. Brand names include Photo-Flo, Triton-X 100 and Igepal. Directions for the proper use of these cleaners can also be provided by the supply house. Soapstone should never be cleaned with anything but water.

Even if a detergent is necessary, begin by thoroughly wetting the stone with water. Pre-wetting the stone prevents the cleaning solution from penetrating too far into the porous surface of the stone, and may improve the efficiency of the cleaning agent. Gently scrub it with a soft brush. Scrubbing from the bottom up prevents streaks. Always dilute the cleaner with the recommended amount of water and rinse often with plenty of clean water. Never let any detergent dry on the surface of the stone.

A wooden stick such as an ice cream stick or tongue depressor will help clean crevices on slate or granite stones. Don't use anything other than a toothbrush on softer stones such as marble or sandstone. Never use metal implements of any kind.

Household ammonia can also be used to clean stones with biological growth such as lichen, but should be used as a second choice when non-ionic detergents don't provide effective results. If you use ammonia, do not exceed one cup ammonia to four cups water. Some conservators recommend not removing lichen as the procedure can open the pores of the stone to a new, and worse, invasion. However, some forms of lichen are acidic in nature, not only obscuring the epitaph and icon, but actually eating into the surface of the stone. Lichen removal must be determined on a case-by-case basis.

Other types of biological growth, such as stubborn black algae, can be removed by using calcium hypochlorite. [Webmaster note: As of 2021 calcium hypochlorite is no longer recommended due to potential damage to marble stones.] This is available as swimming pool disinfectant. This is a granular product not to be confused with other swimming pool disinfectants such as "liquid chlorine" or sodium hypochlorite. Dissolve one pound of calcium hypochlorite in four gallons of warm water. Use only to remove biological growth. Follow the cleaning procedure described above.

Finally, never attempt to clean a stone that appears to be distressed. This is indicated by cracks, flaking, scaling, or a "sugary" (granular) surface. Tap the stone gently to make sure there are no internal hollow areas. If you have any doubt about the stone's ability to withstand the cleaning procedure, don't attempt it.

Gravestone repair is a difficult subject to address because we have not yet established perfect preservation or conservation methods. Best practices are still being developed, and there is still some debate over which techniques can safely be used. For instance, though we know for certain that cement is detrimental to old stones, we don't yet know what the long term effects of epoxy are.

The information presented here is the best available to our present knowledge. In general we recommend that only reversible methods be used. This will allow us to take advantage of better techniques as they are developed in the future. And above all, the best rule of thumb is to do no harm.

Cement. The use of cement in any type of repair is detrimental to the stone. Despite this fact, it is one of the most commonly used methods. Sometimes broken or fragmented stones are encased in cement. This has two unfortunate results. First, the chemicals in the cement can affect the stone. They may eat away at the stone or cause yellowing. The second is that most of the materials used to create historic gravestones (slate and marble for instance) are much softer than cement, and often brittle. As the New England weather gets warmer and cooler the gravestone expands and contracts. Because the slate is weaker than the cement, the stone cracks while the cement remains in pristine condition. Furthermore, the process of embedding stones in concrete is irreversible. If in the future we find a better way of repairing these stones, we won't be able to remove them from the concrete. Sometimes fallen stones are set in a base of concrete in order to get them upright. Unfortunately, the cement provides a conduit allowing the stone to absorb water from the ground. Lime from the cement wicks into the stone as well. The water then freezes and expands, sometimes causing damage to the surface of the stone, often causing it to snap off at the base.

Preservative Sealers. Never apply any type of sealer to a gravestone. The sealer will eventually fail and cause a layer of moisture to form between the surface of the gravestone and the (supposed) protectant. Because the stone cannot breathe, the moisture builds up and causes the surface of the stone to discolor and eventually flake away.

Steel Supports and Pins. Never drill into the stone in order to affix supports. Drilling weakens the stone. Steel supports rust and cause irreversible and unsightly damage and discoloration.

Epoxy/Polyester Resins. Some professionals feel that epoxies and resins may be used safely. Others are concerned about the reversibility of this method. Because there is some doubt as to whether it is an appropriate repair method, we recommend that epoxy only be used as a last resort. Keep in mind that there are specific formulas developed for different types of stones. For instance, epoxies designed especially for granite work best with granite. Polyester resins are typically most suitable for marble. In both cases, sunlight causes the material to deteriorate, and discoloration of the stone may occur.

Recommended Materials and Techniques. There are two basic methods of caring for broken gravestones. Stones which are broken in half horizontally, with the base still grounded can be repaired using high quality stainless steel sleeves that hug the vertical edges of the stone. The sleeves are held in place with small amounts of epoxy. There are some nice examples of this method in Forest Hill Cemetery, East Derry, New Hampshire. Another method is the aluminum Nelson Stone Brace which was developed in 2001 and which provides support without the use of pins, cement or epoxy. (For more information on the Nelson Stone Brace see Section V). Keep in mind that both aluminum and stainless steel expand and contract with changes in temperature. The sleeve (or brace) must be carefully fitted so that the support does not crack the stone.

Fragmented stones, and stones that are vertically broken need a different preservation technique. We do not yet have a suitable method of repairing these stones. We recommend the following procedure to protect the fragments and keep them together: build a wooden frame that is six to eight inches deep depending on the thickness of the stone. It must be large enough for the stone to lay flat. The bottom of the frame should have a stainless steel screen for drainage. Place a layer of clean gravel in the bottom of the frame. Place the stone fragments on top. Use additional gravel to hold the fragments in place. The frame assembly may be slightly slanted to facilitate drainage. It should be noted that the frame will eventually rot and will need to be replaced.

In the case of a stone that is unbroken, but leaning dangerously, we recommend the following method. Dig down into the soil until the stone has been loosened enough to gently pull it into position. This can be a sizeable undertaking as the base of the stone may be nearly as large as the portion that's above ground. Hold the stone securely in place with gravel or small stones and brick fragments as shown in the diagram below. Never pack the base of the marker with cement. As temperatures fluctuate, the cement will exert pressure on the base of the stone and cause it to snap off below ground level. The gravel provides both adequate support and good drainage.

A similar procedure can be used for stones that have sunken and need resetting. Dig gently to loosen earth on one side of the stone only. Leaving the earth in place on the other side will provide much needed support, as well as a firm surface against which to reset the stone. The next step is to lift the stone out of the ground. Sometimes this can be done by four strong people. At other times, bars and levers must be used, much the same way they were originally placed in the ground. Lay the stone gently on level ground. This is a good time to explore the base of the stone for identifying marks such as the carver's initials. Prepare a bed for the butt of the stone using bricks. Level them carefully and cover them with a bed of sand as a cushion. Reset the stone against the compacted soil and fill the hole as indicated in the diagram below

In the case of a marble stone that has slipped out of its slot, simply clean the slot and put it back in. Use existing pins if possible, and epoxy only if necessary. If the base of the stone has broken off and is still in the slot it may need to be chiseled out, or you may want to consult a professional.

Control of plant and tree growth is critical to graveyard restoration. The objective is to prepare the site for regular maintenance by equipment such as a small mower and trimmer. We suggest a listing of all plants found in the graveyard, both woody and herbaceous. Then, decide what you want to keep and what you want to remove. Plan carefully. It's important to study and evaluate each species. For instance, cutting down a softwood tree is an easy procedure. But cutting down a hardwood tree will lead to endless sprouting. In order to avoid this, the stump and major roots must be removed. Other challenges include sumac, lilac, sassafras and some wild roses which spread by underground stolons. Cutting these at the ground level only encourages more sprouting. Poison ivy must be removed while wearing protective clothing. It cannot be burnt as the smoke carries toxins through the air.

Trees need particular consideration. Leaving the deep shade of forest conditions will ensure minimum undergrowth, but falling limbs and trunks can shatter brittle stones and ruin fencing. Trees growing too near the gravestones will cause dislocation. Conversely, grassy sites require the regular maintenance of a lawn mower and trimmer. Keep in mind that any type of power equipment is a potential danger to the stone--care is needed during maintenance.

Keep in mind that an old graveyard may contain old-fashioned plant materials that are worth preserving. Even wild herbaceous plants on the site may be of interest. The Foss Graveyard in Rye illustrates the range of old garden plants that may be found. Pink Scotch Roses filled the entire front end. Also found were Lily-of-the-Valley, Orange Day-lily, Double Soapwort, Star-of-Bethlehem, and Turk's Cap Lily. Wild materials included Tansy, Virginia Rose, and Carrion Flower. Samples of each were retained while unwanted woody plants were eliminated.

Though herbicides can be very effective in removing unwanted plant growth, it is illegal to use these chemicals unless you are either licensed to do so or own the property. Therefore, in most cases, controlling plant growth is largely a matter of cutting and digging.

Simple repairs to stone walls and other historic enclosures (such as granite posts and chains) can often be done by amateurs. We encourage this maintenance as the enclosure is often the only remaining feature of an old gravesite. In addition, the New Hampshire RSAs require suitable fencing in the case of municipal cemeteries. However, since stone wall conservation sometimes requires taking the whole wall down in order to rebuild it, you may need to contract with a professional.

Gates are also an important feature of old graveyards. We recommend that the restoration of iron gates with decorative metal work be done by a professional.

Maintenance is an important part of graveyard restoration. Brush grows back quickly, protective wooden frames rot and must be replaced, stones continue to be affected by age and the elements. Sites may be kept up by neighbors, community members or scouts performing community service projects. Funding may be possible through grants or trust funds established by descendants. Towns may be willing to take responsibility for the graveyard's upkeep. Consultation with town officials and family members will determine which options are open to you in terms of providing routine maintenance to the site.

Each town will deal with its graveyards in a different manner. The restoration may be done as a paid project by town workers, or it may be done entirely by volunteer labor. Some towns have been able to coordinate both paid and volunteer work. In other towns, scouts or other community groups have undertaken projects to compile records or maintain sites. Either way, the project will require careful planning and supervision.

The past few years have given rise to a wealth of reliable information on how to care for our historic graveyards. We encourage the use of these resources in addition to the guidelines provided by this handbook.