Article

Coral as building material in late Portuguese and early Dutch Malacca

From Munshipedia, the MBRAS digital historical encyclopedia

Coral as building material in late Portuguese and early Dutch Malacca

T.T. Khoo, a geologist at the University of Malaya, published this article in the Journal of the Malaysian Branch of the Royal Asiatic Society in 1997, examining the use of coralline material in the construction of St. Paul’s Church, the Santiago Gate, and associated retaining walls on St. Paul’s Hill, Malacca. Drawing on radiocarbon dating, petrographic analysis of construction materials, and contemporary Portuguese and Dutch documents, Khoo argues that coral served as aggregate in concrete, as shaped building stone, and as a source of lime during the late Portuguese and early Dutch periods, and that the material evidence supports a primarily Portuguese origin for the Santiago Gate with only superficial Dutch modification.

Summary

The article addresses a historiographical controversy over the construction and reconstruction of the Santiago Gate and the broader Portuguese fort at Malacca. While Dutch Governor Balthasar Bort reported in 1669 that the gate was rebuilt after its destruction during the 1641 siege, and while Harrison (1985) accepted a Dutch origin dated 1670, de Lima (1989) had presented pictorial and epigraphic evidence that the gate was substantially Portuguese, with the Dutch altering only the date inscription from 1570 to 1670. Khoo contributes independent material evidence to this debate by identifying two distinct generations of cementing material in the walls of both the Santiago Gate and St. Paul’s Church: an early concrete containing coralline aggregates, charcoal, sea shells, and Chinese porcelain sherds, and a later mortar and brick-concrete that overprints the earlier material. The early concrete is attributed to the Jesuit builders who constructed the church between 1566 and 1590, while the later mortar, containing recycled brick fragments and used as void filler, is interpreted as Dutch repair work following the 1641 capture and the earlier 1606 siege of Matelief.

The provenance of the coral is established through two radiocarbon dates—6910 ± 50 years BP and 4720 ± 110 years BP—which rule out the use of living or recently dead reef material and instead point to Holocene raised coral reef terraces in the Strait of Malacca or Sunda Strait region, where sea levels stood 2–4 metres above present between approximately 7500 and 2000 years BP. Khoo further argues that the Portuguese prohibition on stone construction outside the fort, documented by Eredia (1613) and Barretto de Resende (c. 1638), explains the otherwise puzzling use of fragile coral as tombstones at Bukit China during the 16th century, since coral was too friable to serve as a strategic military material and could therefore be permitted for civilian use.

The article also situates the construction practices within the military context of repeated sieges (1568–1629), which necessitated the stockpiling of building materials within the fort and the rapid repair of fortifications between attacks. The preference for massive Porites coral over more delicate species is explained by its durability in high-energy ocean environments, a selection criterion that Khoo notes anticipates modern Pacific coral-concrete engineering principles by over four centuries.

Key Findings

  • Two radiocarbon dates on Porites coral specimens—6910 ± 50 years BP (sample SUA 2404, from the upper benches behind the Santiago Gate) and 4720 ± 110 years BP (sample 96/78, from the early concrete behind the church)—establish that the coral was sourced from Holocene raised reef terraces, not from living or recently dead reefs (pp. 102–103).
  • St. Paul’s Church was constructed by the Jesuits between 1566/1567 and 1590; the Dutch captured Malacca on 14 January 1641, and the church fell into disuse after 1753 when Christ Church was completed (pp. 104–105).
  • The British demolished the Portuguese fort in 1807–1808 at a cost of 260,000 rupees; Munshi Abdullah witnessed fragments “as large as elephants and some as large as houses” blown into the air, attesting to the structural integrity of the laterite-and-coral-concrete construction (p. 109).
  • The Santiago Gate bears the VOC seal and the date “Anno 1670” above the arch, but de Lima (1989) demonstrated that the original Portuguese inscription read “Anno 1570” and that the access route was modified to an “S” shape after the visit of architect Cairato in 1588; Khoo’s identification of two generations of concrete in the gate’s walls corroborates a primarily Portuguese structure with Dutch repair (pp. 107, 109).
  • Eight sieges or blockades of Malacca are recorded between 1568 and 1629, including the three-month Dutch siege of Matelief in 1606 and a five-month Aceh siege in 1629, creating the military imperative for stockpiled building materials within the fort (p. 106, Table 1).
  • Bort’s 1679 report records 185 brick houses in Malacca, suggesting that the Portuguese prohibition on stone construction outside the fort was relaxed during the Dutch period (p. 109).

Conclusion

Khoo’s definitive takeaway is that the material evidence from St. Paul’s Hill—specifically the stratigraphic relationship between the two generations of concrete and the Holocene age of the coral—provides independent corroboration for de Lima’s (1989) argument that the Santiago Gate is fundamentally a Portuguese structure, with the Dutch contribution limited to superficial repairs and the alteration of a single date inscription. The article further demonstrates that Portuguese builders in Malacca had empirically determined that massive Porites coral produced a durable concrete suitable for tropical fortification, a practical insight that prefigures modern Pacific coral-concrete engineering by more than four centuries.

Context

  • The study draws on primary Portuguese sources (Cardon 1934, 1947; Eredia 1613; Barretto de Resende c. 1638; Jesuit letters via Schurhammer 1934) and Dutch sources (Leupe via Hacobian 1936; Bort via Bremner 1927), combined with original fieldwork and radiocarbon dating conducted by the author.
  • The article’s historiographical contribution lies in introducing geological and archaeological methods—radiocarbon dating, petrographic analysis of construction materials, and stratigraphic interpretation of cementing layers—as independent evidence to adjudicate a debate previously conducted solely on the basis of documentary and epigraphic sources.

References