One of the strangest mysteries in archaeology was discovered in
the Diquis Delta of Costa Rica. Since the 1930s, hundreds of stone balls have been documented,
ranging in size from a few centimetres to over two meters in
diameter. Some weigh 16 tons. Almost all of them are made of granodiorite, a hard,
igneous stone. These objects are monolithic sculptures
made by human hands.
Balls in the Courtyard of National Museum, San José, Costa Rica.
Photo courtesy of John W. Hoopes.
Copyright ©2001 John W. Hoopes. All rights reserved.
The spheres number over 300. The large ones weigh many tons.
Today, they decorate official buildings such as the Asamblea
Legislativa, hospitals and schools. You can find them in museums.
You can also find them as ubiquitous status symbols adorning the
homes and gardens of the rich and powerful.
The stones may have come from the bed of the
, to where they were transported by natural processes from sources
of parent material in the Talamanca mountains. Unfinished
spheres were never found. Like the monoliths of the Old World, the
Costa Rican quarry was more than 50 miles away from the final
resting place of these mysteries.
WERE COSTA RICAN SPHERES ANCIENT
Debunking the "Mystery" of the Stone Balls
by John W. Hoopes
The stone balls of Costa Rica have been the object of
pseudoscientific speculations since the publication of Erich von
Däniken's Chariots of the Gods
in 1971. More recently, they have
gained renewed attention as the result of books such as Atlantis in America- Navigators of the Ancient World, by Ivar Zapp and George
Erikson (Adventures Unlimited Press, 1998), and The Atlantis
Blueprint: Unlocking the Ancient Mysteries of a Long-Lost
Civilization, by Colin Wilson and Rand Flem-Ath (Delacorte Press,
2001). These authors have been featured on television, radio,
magazines, and web pages, where they do an incredible disservice to
the public by misrepresenting themselves and the state of actual
knowledge about these objects.
Although some of these authors are often represented as having
"discovered" these objects, the fact is that they have
been known to scientists since they first came to light during
agricultural activities by the United Fruit Company in 1940.
Archaeological investigation of the stone balls began shortly
thereafter, with the first scholarly publication about them
appearing in 1943. They are hardly a new discovery, nor are they
especially mysterious. In fact, archaeological excavations
undertaken at sites with stone balls in the 1950s found them to be
associated with pottery and other materials typical of the
Pre-Columbian cultures of southern Costa Rica. Whatever
"mystery" exists has more to do with loss of information
due to the destruction of the balls and their archaeological
contexts than lost continents, ancient astronauts, or transoceanic
Hundreds of stone balls have been documented in Costa Rica,
ranging in size from a few centimeters to over two meters in
diameter. Almost all of them are made of granodiorite, a hard,
igneous stone. These objects are not natural in origin, unlike the
stone balls in Jalisco, Mexico that were described in a 1965
National Geographic article. Rather, they are monolithic sculptures
made by human hands.
The balls have been endangered since the moment of their
discovery. Many have been destroyed, dynamited by treasure hunters
or cracked and broken by agricultural activities. At the time of a
major study undertaken in the 1950s, fifty balls were recorded as
being in situ. Today, only a handful are known to be in their
by John W. Hoopes
Where are the balls found?
They were originally found in the delta of the Térraba River,
also known as the Sierpe, Diquís, and General River, near the towns
of Palmar Sur and Palmar Norte. Balls are known from as far north as
the Estrella Valley and as far south as the mouth of the Coto
Colorado River. They have been found near Golfito and on the Isla
del Caño. Since the time of their discovery in the 1940s, these
objects have been prized as lawn ornaments. They were transported,
primarily by rail, all over Costa Rica. They are now found
throughout the country. There are two balls on display to the public
in the U.S. One is in the museum of the National Geographic Society
in Washington, D.C. The other is in a courtyard near the Peabody
Museum of Archaeology and Ethnography, at Harvard University in
How big are they?
The balls range in size from only a few centimeters to over two
meters in diameter. It has been estimated that the largest ones
weigh over 16 tons (ca. 15,000 kg).
What are they made of?
Almost all of the balls are made of granodiorite, a hard, igneous
stone that outcrops in the foothills of the nearby Talamanca range.
There are a few examples made of coquina, a hard material similar to
limestone that is formed from shell and sand in beach deposits. This
was probably brought inland from the mouth of the Térraba-Sierpe
delta. (The background image for these pages is a photograph of the
surface of a stone ball in Palmar Sur, Costa Rica.)
How many of them are there?
Samuel Lothrop recorded a total of approximately 186 balls for
his 1963 publication. However, it has been estimated that there may
be several hundred of these objects, now dispersed throughout Costa
Rica. It was reported that one site near Jalaca had as many as 45
balls, but these have now been removed to other locations.
How were they made?
The balls were most likely made by reducing round boulders to a
spherical shape through a combination of controlled fracture,
pecking, and grinding. The granodiorite from which they are made has
been shown to exfoliate in layers when subjected to rapid changes in
temperature. The balls could have been roughed out through the
application of heat (hot coals) and cold (chilled water). When they
were close to spherical in shape, they were further reduced by
pecking and hammering with stones made of the same hard material.
Finally, they were ground and polished to a high luster. This
process, which was similar to that used for making polished stone
axes, elaborate carved metates, and stone statues, was accomplished
without the help of metal tools, laser beams, or alien life forms.
Who made them?
The balls were most likely made by the ancestors of native
peoples who lived in the region at the time of the Spanish conquest.
These people spoke Chibchan languages, related to those of
indigenous peoples from eastern Honduras to northern Colombia. Their
modern descendants include the Boruca, Téribe, and Guaymí. These
cultures lived in dispersed settlements, few of which were larger
than about 2000 people. These people lived off of fishing and
hunting, as well as agriculture. They cultivated maize, manioc,
beans, squash, pejibaye palm, papaya, pineapple, avocado, chilli peppers, cacao, and many other fruits, root crops, and medicinal
plants. They lived in houses that were typically round in shape,
with foundations made of rounded river cobbles.
How old are they?
Stone balls are known from archaeological sites and buried strata
hat have only pottery characteristic of the Aguas Buenas culture,
whose dates range from ca. 200 BC to AD 800. Stone balls have
reportedly been found in burials with gold ornaments whose style
dates from after about AD 1000. They have also been found in strata
containing shreds of Buenos Aires Polychrome, a pottery type of the
Chiriquí Period that was made beginning around AD 800. This type of
pottery has reportedly been found in association with iron tools of
the Colonial period, suggesting it was manufactured up until the
16th century. So, the balls could have been made anytime during an
1800-year period. The first balls that were made probably lasted for
several generations, during which time they could have been moved
What were they used for?
Nobody knows for sure. The balls had ceased to be made by the
time of the first Spanish explorers, and remained completely
forgotten until they were rediscovered in the 1940s. Many of the
balls were found to be in alignments, consisting of straight and
curved lines, as well as triangles and parallelograms. One group of
four balls was found to be arranged in a line oriented to magnetic
north. This has led to speculation that they may have been arranged
by people familiar with the use of magnetic compasses, or
astronomical alignments. Unfortunately, all but a few of these
alignments were destroyed when the balls were moved from their
original locations, so measurements made almost fifty years ago
cannot be checked for accuracy. Many of the balls, some of them in
alignments, were found on top of low mounds. This has led to
speculation that they may have been kept inside of houses built on
top of the mounds, which would have made it difficult to use them
for making observations. Ivar Zapp's suggestions that the alignments
were navigational devices pointing to Easter Island and Stonehenge
are almost certainly wrong. Lothrop's original measurements of
alignments of balls only a few meters apart were not accurate or
precise enough to allow one to control for errors in plotting such
long distances. With the exception of balls located on the Isla del
Caño, most of the balls are too far from the sea to have been
useful to ocean-going navigators.
Why are the balls endangered?
Virtually all of the known balls have been moved from their
original locations, destroying information about their
archaeological contexts and possible alignments. Many of the balls
have been blown up by local treasure hunters who have believed
nonsensical fables that the balls contain gold. Balls sitting in
agricultural fields have been damaged by periodic burning, which
causes the once smooth surface of the balls to crack, split, and
erode--a process that has contributed to the destruction of the
largest known stone ball. Balls have been rolled into gullies and
ravines, or even into underwater marine locations (as at Isla del
Caño). The vast majority have been transported far from their zone
of origin, separating them even further from the consciousness of
the descendants of the people who made these balls.
by John W. Hoopes
Several authors have now contributed to widespread misinformation
about the stone balls of Costa Rica, leading to unfounded
speculation about their nature and origin.
The Size of the Balls
In an article in Atlantis Rising Online, George Erikson makes
exaggerated claims for the size of the stone balls, writing that
they are "weighing up to 30 tons and measuring up to three
meters in diameter" According to Samuel Lothrop, author of the
most extensive study of the balls, "A 6-foot ball is estimated
at about 7.5 tons, a 4-foot ball at 3 tons and a 3-foot specimen at
1.3 tons" (1963:22). Lothrop estimated the maximum weight for
ball was around 16 tons. The largest known ball measures 2.15 m in
diameter, which is substantially smaller than three meters.
John W. Hoopes with the largest known
Photo courtesy of John W. Hoopes.
Copyright ©2001 John W. Hoopes. All rights reserved.
The Roundness of the Balls
Erikson also states that these objects "were perfect spheres
to within 2 millimeters from any measurement of both their diameter
and circumference." This claim is false. No one has ever
measured a ball with a sufficient degree of precision to make it.
Neither Ivar Zapp nor George Erikson has proposed a methodology by
which such measurements could be made. Lothrop (1963:17) wrote:
"To measure the rotundity we used two methods, neither
completely satisfactory. When the large balls were deeply buried in
the ground, it might take several days to trench around them. Hence,
we exposed the upper half only and then measured two or three more
diameters with tape and plumb bob. This revealed that the poorer
specimens, usually with diameters ranging between 2 and 3 feet
(0.6-0.9 meters), varied in diameters as much as one or 2 inches
(2.5-5.1 centimeters)." It should be clear that this method
assumed that the portion under ground was spherical. Lothrop also
measured balls that were more completely exposed by taking up to
five circumferences with a tape measure, from which he then
calculated their diameters. He writes, "Evidently, the larger
balls were the product of the finest craftsmanship, and they were so
nearly perfect that the tape and plumb-bob measurements of diameters
did not reveal imperfections. Therefore, we measured circumferences
horizontally and, if possible, at a 45-degree upward slant toward
the four cardinal points. We did not usually ascertain the vertical
circumference as the large balls were too heavy to move. This
procedure was not as easy as it sounds because several people had to
hold the tape and all measurements had to be checked. As the
variation in diameters was too small to be detected by eye even with
a plumb bob, the diameters have been computed mathematically".
The source of claims for precise measurements may stem from
misinterpretations of Lothrop's tables, in which he presents the
calculated diameters in meters to four decimal places. However,
these are mathematically calculated estimates, not direct
measurements. They have not been rounded to reflect the actual
precision with which the actual measurements were taken. It should
be obvious that differences "too small to be detected by
eye" cannot be translated into claims about precision "to
within 2 millimeters". In fact, the surfaces of the balls are
not perfectly smooth, creating irregularities that plainly exceed 2
millimeters in height. As noted above, some balls are known to vary
over 5 cm (50 mm) in diameter. In the photograph of the largest ball
on this web site, it is clear that the surface has been badly
damaged. It is therefore impossible to know how precisely formed
this ball might have been.
The Makers of the Balls
George Erikson states that "archaeologists attributed the
spheres to the Chorotega Indians". No archaeologist familiar
with the evidence has ever made this claim. The Chorotega were an
Oto-Manguean speaking group that occupied an area of Guanacaste,
near the Gulf of Nicoya in northwestern Costa Rica. The peoples who
lived in the area where the balls are found were Chibchan speakers.
The balls have been found in association with architectural remains,
such as stone walls and pavements made of river cobbles, and both
whole and broken pottery vessels that are consistent with finds at
other sites associated with the Aguas Buenas and Chiriquí cultures.
These are believed to represent native peoples ancestral to
historical Chibchan-speaking group of southern Costa Rica.
The Dating of the Balls
George Erikson and others have implied that the balls may date as
early as 12,000 years ago. There is no evidence to support this
claim. Since the balls cannot be dated directly by methods such as
radiocarbon dating, which can be applied directly only to organic
materials, the best way to date them is by stratigraphic context and
associated artifacts. Lothrop excavated one stone ball that was
located in a soil layer separated from an underlying, sherd-bearing
deposit that contained pottery typical of the Aguas Buenas culture
(200 BC - AD 600). In the soil immediately beneath this ball he
found the broken head of a painted human figurine of the Buenos
Aires Polychrome type, dated to AD 1000-1500 (examples have
reportely been found associated with iron tools). This suggests the
ball was made sometime between AD 600 and 1500.
The Balls are "Out of Context"
Since their discovery in 1940, the vast majority of these balls
have been removed from their archaeological contexts to serve as
lawn ornaments across Costa Rica. Many of the balls studied by
Lothrop appeared to have rolled off of nearby mounds. Several had
been covered by layers of fine silt, apparently from flood deposits
and natural erosion. Naturally, they are "out of context"
in the sense of having few good archaeological associations.
Scholars Have Ignored Them
It is not unusual for authors who write about the stone balls to
claim that these objects have received inadequate attention from
serious scholars. While this is undoubtedly true, it is not true
that these objects have been ignored. It is also not true that
scholarship regarding them has been somehow hidden from the general
public. The first scholarly study of the balls was undertaken by
Doris Stone immediately upon their discovery by workers for the
United Fruit Company. Results of her investigation were published in
1943 in American Antiquity, the leading academic journal for
archaeology in the United States. Samuel Lothrop, an archaeologist
on the staff of the Peabody Museum of Archaeology and Ethnography at
Harvard University, undertook major fieldwork concerning the balls
in 1948. The final report on his study was published by the Museum
in 1963. It contains maps of sites where the balls were found,
detailed descriptions of pottery and metal objects found with and
near them, and many photographs, measurements, and drawings of the
balls, their alignments, and their stratigraphic contexts.
Additional research on the balls by archaeologist Matthew Stirling
was reported in the pages of National Geographic in 1969. In the
late 1970s, archaeological survey on Isla del Caño (published in
1986) revealed balls in offshore contexts. Sites with balls were
investigated and reported in the 1980s by Robert Drolet in the
course of surveys and excavations in the Térraba Valley. In the
late 1980s and early 1990s, Claude Baudez and his students from the
University of Paris returned to the locations of Lothrop's earlier
fieldwork in the Diquís delta to undertake a more careful analysis
of the pottery of the area, producing more refined dates for the
contexts of the balls. This research was published in Spanish in
1993, with an English summary appearing in 1996. Also in the early
1990s, the author undertook fieldwork around Golfito, documenting
the existence of the easternmost examples of these balls. At this
time, Enrico Dal Lago, a student at the University of Kansas,
defended a Master's thesis on the subject of the balls. The most
careful study of the balls, however, has been fieldwork undertaken
from 1990-1995 by archaeologist Ifigenia Quintanilla under the
auspices of the National Museum of Costa Rica. She was able to
excavate several balls in situ, documenting the process of their
manufacture and their cultural associations. Quintanilla's research
has been the most complete field study of these objects since
Lothrop. While still mostly unpublished, the information she
collected is currently the subject of her graduate research at the
University of Barcelona. Even with current research pending, the
list of references on this Web site makes it clear that the stone
balls have received a great deal of serious, scholarly attention.
The content of the article above is ©2001 by John W. Hoopes.
All rights reserved. Reprinted by Permission.