Week of March 30: Excalibur Sword Verified as 12th Century Relic, Second Giza Sphinx Claims, and More

Material analysis has confirmed the legendary “Excalibur” sword embedded in stone at Tuscany’s Chapel of Montesiepi dates to the late 12th century, bringing scientific validation to a centuries-old legend. Meanwhile, Italian researchers using ground-penetrating radar claim to have detected a second buried Sphinx beneath the Giza Plateau, though the unverified findings have faced skepticism from an archaeological community demanding peer-reviewed evidence. New genetic research has also established that pre-Columbian contact between Polynesians and Native Americans occurred around AD 1200, with Native American ancestry comprising approximately 8% of several Polynesian populations’ genomes.

Artifact Discoveries

The sword embedded in stone at the Chapel of Montesiepi in Tuscany—famous as a potential real-world counterpart to the legendary Excalibur—has been verified through material analysis as consistent with weapons designed in the late 12th century [1]. This finding represents a significant intersection between medieval legend and archaeological science. Chemical analysis conducted on the blade has confirmed its compatibility with weaponry from this period, though the specific metallurgical testing methods employed remain only partially documented in available sources. The verification was led by Luigi Garlaschelli of the University of Pavia, bringing formal scientific methodology to what had long been dismissed as mere folklore [1].

12th century sword embedded in Tuscan stone verified genuine by material analysis

While the location is firmly established at the Chapel of Montesiepi near San Galgano, several aspects of the investigation remain poorly documented in accessible sources [2]. Ground penetrating radar surveys have reportedly detected a hidden cavity beneath the stone slab, described as approximately 2 meters by 1 meter in dimension, potentially indicating an undisturbed burial. Some reports suggest drilling was conducted to verify continuity between the exposed and hidden portions of the blade. However, key questions persist: whether independent peer-reviewed publication of the methodology exists, what specific alloy composition was identified, and whether the site corresponds precisely to the Montesiepi Chapel referenced in some accounts. The distinction between these names and their geographic relationship requires further verification.

SAR scan technology methodology and need for independent verification

Remote Sensing & Technology

Italian researcher Filippo Biondi has claimed that ground-penetrating radar scans reveal a potential second Sphinx buried beneath a sand mound on the Giza Plateau, positioned to mirror the famous original monument [9][8]. The Italian team employed advanced imaging technology including SAR imaging combined with Doppler tomography for their subsurface analysis, technology that some experts consider similar to previous pyramid surveys. However, the scanning methodology and equipment used are proprietary, which has prevented independent verification of these claims [9].

Second sphinx discovered beneath Giza Plateau using ground-penetrating radar

Despite the intriguing radar data, no peer-reviewed study supports the theory, no excavation has taken place, and the broader archaeological community remains skeptical of the unverified findings [7][5][6]. Interestingly, a 2007 study by Egyptologist Bassam El Shammaa documented that two sphinxes did exist on the Pyramids plateau [3], providing historical context for the contemporary debate. Yet significant questions remain: the specific dimensions and exact location of the proposed second sphinx based on radar data are not publicly documented, and experts emphasize that subsurface anomalies detected through remote sensing could represent natural geological formations, later intrusions, or imaging artifacts rather than an intentional buried structure. Until independent verification and peer-reviewed publication occur, the claim of a buried second Sphinx at Giza remains a speculative proposition lacking substantial empirical support.

SAR (Synthetic Aperture Radar) technology operates as an active remote sensing method, with satellites approximately 400 miles above Earth sending electromagnetic pulses toward the ground and recording the reflected signals that return [10][12]. Filippo Biondi and his team developed their SAR-based subsurface detection approach through years of study examining underground bridges and structures in Italy before applying the methodology elsewhere, including the Giza Plateau at the persuasion of Armando Mei [10]. However, a significant tension exists in the claimed capabilities: while proponents assert the technology can detect underground voids by analyzing frequency changes when signals encounter solid rock versus cavities, this capability is contested by documented limitations. According to peer-reviewed literature, SAR suffers from “poor penetrating action of electromagnetic waves inside solid bodies” [11], raising questions about how any methodology might overcome this fundamental physical constraint to reliably detect deep subsurface structures. A terminology inconsistency also exists—the podcast description of “sound activity frequency changes” conflates acoustic detection methods with electromagnetic SAR technology, suggesting imprecise communication of the underlying physics.

This unresolved tension has prompted calls for independent verification, with Stanford Research Institute expressing interest in replicating the findings and an Italian university seeking permission from Egyptian authorities to conduct its own remote sensing work [10]. Compounding the uncertainty, Biondi’s peer-reviewed papers on the SAR methodology and findings have faced resistance and publication difficulties, leaving the scientific community without established benchmarks against which to evaluate the claims [10]. The fundamental question of how Biondi’s approach might achieve what conventional SAR processing cannot—reliable deep subsurface void detection despite acknowledged electromagnetic penetration limitations—remains formally unanswered in available sources.

Architecture & Monuments

Volkonsky Dolmen stands as one of the most remarkable dolmen monuments in the Caucasus, distinguished by its remarkable monolithic construction carved from a single massive block of sandstone—a technique that sets it apart from other regional dolmens, which were typically built from assembled stone slabs [13]. The interior chamber rises approximately 1.5 meters in height and features a perfectly circular entrance, hollowed out through what must have required considerable time and coordinated effort from its Bronze Age builders [13]. Most archaeologists date this enigmatic structure to the 3rd or 2nd millennium BC, placing it within the late Neolithic to Bronze Age period when dolmen construction was flourishing throughout the Caucasus region [13].

Volkonsky Dolmen: unique monolithic chamber carved from single sandstone block in Caucasus

What makes Volkonsky Dolmen particularly puzzling to researchers is the absence of human remains and no evidence of secondary burial use—features commonly associated with dolmen monuments elsewhere [13]. The builders clearly possessed the technical capability to use simpler slab construction methods that were already established in the region, yet they chose the far more demanding monolithic approach [13]. This deliberate choice, combined with the structure’s apparent lack of funerary function, raises fundamental questions about its original purpose. Without diagnostic artifacts or clear archaeological context, scholars remain uncertain whether the monument served a ritual, communal, or entirely different social function that left no material trace of burials [13].

In Brief

Sheila Coulson of the University of Oslo led excavations at Rhino Cave, located among the Tsodilo Hills of Botswana—a remote rock outcrop rising above otherwise flat Kalahari terrain, the only such formation for over 100 kilometers [17]. Excavations yielded approximately 13,000 artifacts, including spearheads fashioned from multicolored stones sourced from considerable distances, with twenty-two red stone spearheads appearing purposefully burnt—a pattern Coulson interpreted as ritual destruction [17][18]. Radiocarbon dating of organic materials from cave deposits returned ages of approximately 15,000 years [17]. Some indentations are covered by flowstone while others appear fresh, making it impossible to date the carvings to a single period [21][17]. Between roughly 3500 and 1000 BCE, red ochre burial practices and marine shell artifacts reveal extensive trade networks spanning most of North America, though the earlier 4500 BCE boundary commonly cited for this phenomenon remains unsupported in available sources. Red ochre burials have been documented from Kentucky and Tennessee eastward through the northern Great Plains to California, while marine shells traveled even greater distances—conch shells sourced from the West Indies appeared in burials as far north as New York’s Finger Lakes region, and abalone shells from Southern California circulated through prehistoric exchange systems reaching far into the continent’s interior [22]. While sources document shell transfer across vast distances, the specialists identified no stable isotope data, trace element analysis, or neutron activation studies confirming West Indies conch or Southern California abalone sourcing—these origins may be inferred rather than chemically demonstrated [22]. Open questions persist regarding whether these networks operated continuously or intermittently, whether they constituted a single exchange system or multiple discrete relationships, and what the symbolic significance of red ochre in burial contexts may have been [22]. Precisely dated to 18 million years ago, this specimen comes from an area that functioned as a biogeographic crossroads between Africa and Eurasia during the Early Miocene [27]. The fossil challenges long-standing assumptions that East Africa was the primary center of early ape evolution, providing tangible evidence that the underexplored northeastern part of Afro-Arabia may have played a far more significant role in crown Hominoidea origins than previously recognized. While the specific taxonomic identification of the Egyptian fossil remains to be fully established, its existence underscores how sampling bias can influence our understanding of deep human origins [27]. A unique porthole stone discovered at Göbekli Tepe stands out from other similar artifacts at both Göbekli Tepe and Karahantepe due to its larger size, more ornate craftsmanship, and distinctive features: it is flanked by guardian beasts and contains two doors [30]. Despite its extraordinary significance, archaeologists wrapped the stone in plastic, sifted the burial dirt, and reburied it in situ at the discovery location—a practice that, while protecting the artifact, also prevents scientists from conducting further tests or gathering new information [30]. In 2010, a statue depicting a human head with a vulture perched on top was stolen directly from the ground during excavation, prompting the Turkish government to fine then-site director Klaus Schmidt approximately $10,000 [30]. The Karnak Temple Complex maintained a continuous presence in human memory unlike many ancient monuments that were lost and later rediscovered [31]. The complex comprises a vast assortment of temples, pylons, chapels, and other structures near Luxor [33], expanded through near-constant construction by Egyptian rulers over centuries [32]. Yet the site experienced considerable degradation: parts were systematically dismantled and repurposed as building material throughout the Nile Valley, and earthquakes toppled columns [31]. Genetic research has firmly established that a single pre-Columbian contact event between Polynesians and Native Americans occurred around AD 1200, leaving detectable traces in modern and ancient genomes. A landmark study by Ioannidis and colleagues found that Native American genetic ancestry comprises approximately 8% of the genome in several Polynesian populations, indicating significant gene flow from South America into eastern Polynesia [45]. The timing of this contact predates the settlement of Easter Island, with Fatu Hiva in the Marquesas Islands identified as a likely location of earliest contact [36]. DNA evidence confirms pre-Columbian contact between South America and Polynesia

The directionality of this contact remains contested—genetic evidence shows Native American ancestry in Polynesian populations, but cannot definitively establish whether Polynesians reached South America, Native Americans traveled eastward, or both scenarios occurred [45]. In 1999, a remarkable astronomical alignment was documented at the Baltray standing stones near the Boyne estuary in County Louth, where two thin, flat-sided stones stand approximately 3 metres and over 2 metres in height respectively. Local researcher Michael Byrne first noticed the alignment during summer 1999 by placing binoculars along the edge of the larger southern stone, then observed it again at the winter solstice, before consulting archaeoastronomer Richard Moore and Michael Burn, who confirmed the finding in December 1999 that the larger stone precisely marks the winter solstice sunrise over Rockabill Island, the pair of small islands visible off the coast near Skerries in County Dublin [1] [6] [8]. Similarly, while Anthony Murphy argues for a Neolithic date for the site’s astronomical alignment, Irish archaeologists typically date standing stones to the Bronze Age, meaning the site’s chronology remains formally unresolved, with no radiocarbon dating yet applied to the stones themselves [3] [5]. The simultaneous burning of every major Minoan palace on Crete around 1450 BC—approximately 150 years after the catastrophic Thera eruption—had long baffled archaeologists before recent research finally provided firmer dating for this destruction event [57]. The scale of destruction was total: no major palace complex survived this event, suggesting a coordinated phenomenon rather than isolated incidents. By 1400 BC, only Knossos had been rebuilt, and it emerged as a transformed center: the rebuilt palace now used Mycenaean Linear B script in place of the indigenous Minoan Linear A, signaling that mainland Greek administrators had assumed control of the island’s administrative machinery [57]. Rock-cut tombs across Europe reveal a remarkable chronological range, from Sicily’s Cava Dispica around 20th century BC to Heysham in northern England by the 11th century AD [58][60]. The Iberian Peninsula contains what researchers describe as the largest and most impressive collection of these monuments on the continent, with sites like Panoias in Portugal even featuring Roman inscriptions carved directly into the burial chambers [58]. Importantly, scholars note that no osteological analyses, skeletal remains, or genetic data have been published for these sites, leaving significant gaps in our understanding of the people interred within them [58]. The 3,000-year gap between the earliest and latest examples raises critical questions about whether this represents a continuous tradition or distinct, unrelated cultural practices adopted independently across different regions and periods [58].

Week of March 30: Excalibur Sword Verified as 12th Century Relic, Second Giza Sphinx Claims, and More

Artifact Discoveries

Remote Sensing & Technology

Architecture & Monuments

In Brief

Sources