Longquan Cave

Longquan Cave (33°47’24”N, 111°36’28”E) is located in Longquan Mountain Park in Luanchuan County, Henan Province, China (Figure 1). The site was discovered by the Luanchuan Cultural Relics Administrative Institute, and a systematic investigation was conducted in the spring of 2011 by a joint archaeological team from Beijing Normal University and Luoyang city. During the excavations, stone artefacts, animal bones and a two-layer hearth were uncovered, as well as a unique bone point.

Figure 1.

The location of Longquan Cave in Luanchuan County, Henan Province.

The immediate environment of Luanchuan County, in the west of Henan Province, is the Funiu Mountain area. Mountains and valleys cover the majority of this region. The rivers mostly flow into the Yihe River, which eventually joins the Yellow River via the Luohe River. A small number of streams flow westwards into the Hanshui River. The major soil types lie over Precambrian metamorphic and magmatic rocks, with some Cenozoic exposures along the valley sides.

Longquan Cave faces east, and is situated about 6m above the Yihe River. The cave is heavily damaged by erosion and by recent quarrying of its limestone roof and walls. The remainder of the roof is partly collapsed and the sediments in the central part of the exposed area have been washed away (Figures 2 & 3). Preserved layers were found at the back of the cave near the southern, western and northern walls. The site was excavated within a grid of 1m² sections and subdivided into zones A–D (Figure 2). Zone C had the deepest stratigraphy, followed by zones B, A and D, which are briefly described here.

Figure 2.

Cross-section of the different zones inside Lonquan Cave.

Figure 3.

Longquan Cave (photograph credit: Shuisheng Du).

Zone A: Near the current south-west entrance, this was the largest of the three excavated zones, with an area of around 8m² excavated in 50mm arbitrary spits. It revealed the northern edge of a double hearth that had been destroyed when the front area of the cave was quarried. Most of the cultural remains were retrieved from the southern, interior part of this zone.

Zone B: Due to safety concerns arising from the partially collapsed roof, the deposits in this area were not excavated.

Zone C: Zone C was located in the lowermost area of the cave adjacent to zone D. It too covered an area of around 8m², but only a small portion could be excavated. The uppermost 0.8m of the deposit extended over only around 3–4m², and the lowest part, the infill of a crevice (Figure 2), had an area of less than 1m². Very few artefacts and bones were found in this infill, which was labelled layer 3.

Zone D: This was the smallest excavated zone, with an area of about 1.5–2.5m². It was near the cave wall and unlikely to have been a location of intense occupation, but served as a discard zone.

A total station was used to plot all the artefacts and bones in three dimensions, including, where possible, the inclination and orientation of the stone artefacts and animal bones. All excavated deposits were sieved through a 2mm mesh, allowing the recovery of a large number of stone chips, bone flakes, tooth fragments and rodent bones.

The layers that were recognised are shown in Figure 2 and described as follows:

Layer 1: In zone A this was primarily composed of pebbles and brownish-yellowish clay, 0.33–1.05m thick; in zone C it was a loose, yellowish, silty clay, 0.3–0.67m thick; and in zone D, it was only 50–150mm thick, severely disturbed by subsequent taphonomic and post-depositional effects. The bones and lithics were the same as those retrieved from the underlying layers.

Layer 2: A hard, reddish-brown clay, around 0.5–0.6m thick, with a few pebbles in some areas. Abundant animal bone and lithics were discovered in this layer.

Two hearths were uncovered in zone A at depths of 100mm and 200mm in layer 2. Charcoal samples were collected from zones A, C and D for radiocarbon dating and indicate a range of approximately 29–43 kya cal BP (Table 1). The majority of the readings, however, are from 29–33 kya. Given the date of 37 kya cal BP for layer 3, it seems that the date of 43 kya cal BP can be attributed to the ‘old wood’ effect.

Table 1.

Radiocarbon dates from Longquan Cave (Henan Province).

† Calibrated with IntCal13 in OxCal v4.2 (Bronk Ramsey 2009; Reimer et al. Reference Reimer, Bard, Bayliss, Beck, Blackwell, Ramsey, Buck, Cheng, Edwards, Friedrich, Grootes, Guilderson, Haflidason, Hajdas, Hatté, Heaton, Hoffmann, Hogg, Hughen, Kaiser, Kromer, Manning, Niu, Reimer, Richards, Scott, Southon, Staff, Turney and van der Plicht2013).

Layer 3: (Zone C) characterised by a light-yellow sand layer with embedded, brownish clay lenses. Around 0.7m of this deposit was excavated, but it contained very few animal bones or lithics.

The superimposed hearths

Two hearths were uncovered in zone A, not far from the original prehistoric entrance of the cave that was destroyed by quarrying. The hearths were observed in the exposed section, before the excavations, as two white ash layers. Subsequent excavations and dating further confirmed that there were two superimposed hearths attributed to different periods.

The upper hearth had a diameter of about 0.5–0.6m. A few brought-in small stones and a couple of older rocks lying on the bottom of the cave surrounded it. Three lenticular layers formed the stratigraphy of the hearth:

1. 1) Viscous, brownish red clay, about 50–100mm thick, and similar to the clay outside the hearth. This layer contained burnt bone fragments and stone artefacts. A ¹⁴C sample from this layer gave a calibrated age of 28873±322 cal BP (Table 1).

2. 2) Cemented layer of burnt bones, stones, stone artefacts, about 150–200mm thick and dark grey in colour. Some burnt stones had been reduced to powder and only their shapes could be recognised.

3. 3) Black ash layer about 10mm thick, comprising a mixture of powder, clay and charcoal. Once this layer was cleaned and the stones removed, a 20–30mm layer of grey-white soil was noted covering a larger hearth beneath.

The lower hearth was 0.8–1m in diameter and further divided into two layers:

1. a) Cemented layer formed from a hardened crust of weathered stones, clay and burnt powder. At its centre was a black and red lens, about 20mm thick; other areas were black or grey, and about 10mm thick. Some burnt bone fragments were also found. A large quantity of burnt bones and stones were found on the surface of this hearth, and at its edge was a granite block that showed no trace of knapping but was broken into three parallel pieces, probably from the heat generated by the fire.

2. b) Pure black ashy deposit, several millimetres thick, that consisted mainly of charcoal. Sample 5, taken from this hearth, produced a radiocarbon date of 39487±420 cal BP (Table 1).

Radiocarbon dates

Radiocarbon dates are shown in Table 1. The age of the lower hearth in zone A is around 40 kya cal BP (sample 3 in Figure 2), and the upper one is around 30 kya cal BP (sample 1). The age of layer 3 in zone C is about 37 kya cal BP (sample 4). The upper part of zone D (sample 2) is dated to 31 kya cal BP, and the lower part (samples 5 and 6) to 33–29 kya cal BP. The wide date range for the deposits of Longquan Cave could in part be explained by the presence of dead wood. In addition, the stratigraphic interval between the two hearths could be shorter; the early date of 40 kya cal BP for the lower one seems excessive. In summary, we estimate that most of the accumulation at the back of the cave should fall in the range of 35–31 kya cal BP. The different nature of the sediments in the crevice within zone C, where rare artefacts were found, means that they could be much older than the main layer above.

The lithic industry

Overall, 512 pieces of flaked stone and 460 faunal elements were recovered. Of these, 164 stone artefacts and 153 faunal specimens came from zone A, 198 stone artefacts and 63 faunal specimens from zone C, and 134 artefacts and 244 animal bones were found in zone D. An additional 12 artefacts were collected when the site was first discovered.

A full technical analysis of the stone artefacts has been published elsewhere in Chinese (Zhou et al. Reference Zhou, Li, Pang and Du2011). These artefacts were mainly made of vein quartz, probably obtained from two localities, which could be divided into three grades according to its quality. The best was grade A—a white quartz with a compact texture from the Yihe riverbed about 3km from the site. Another, inferior, quartz was collected from natural crevices within 100m of the site. The latter can be divided into two grades of B and C according to the number of cracks.

The 496 excavated stone artefacts included 96 cores (14 bipolar, 82 with clear striking platforms) and 60 flakes (2 of which are bipolar, the others are knapping flakes). In addition, 73 stone tools were found comprising 33 scrapers, 3 notches and denticulates, 2 points, 2 awls and borers, 2 burins, 9 hammer stones and 22 burnt cobbles (Tables 2–4). In the preliminary report (Zhou Reference Zhou, Li, Pang and Du2011), 3 cobbles, and 31 hammers and stone anvils were listed. Following a re-examination, however, 22 of these artefacts are now recognised to show no indications of knapping, but signs of burning that caused larger nodules to fracture into smaller pieces; these are now listed as ‘burnt items’. They are all granite apart from one that is composed of a coarse sandstone. As we did not find any cores or flakes made from these rocks, we assume that these are fire-cracked rocks or pot boilers (e.g. Gao et al. Reference Gao, Guan, Chen, Yi, Pei and Wang2014).

Table 2.

Tool types of zones A, C, D and ‘others’, collected when the site was first investigated (see Figure 4 for examples of some of the tool types).

Table 3.

Debitage of zones A, C, D and ‘others’, collected when the site was first investigated.

Table 4.

Cores of zones A, C, D and ‘others’, collected when the site was first investigated.

There were also 58 broken flakes, 225 chunks and many debitage fragments: 1327 were over 20mm long; 16854 were 5–20mm in length; chips under 5mm in size were not counted because there were so many. They are, however, the best indication of the in situ knapping practised inside the cave.

The manufacturing process of the stone assemblage in Longquan Cave would be described as a simple ‘core-and-flake’ technique. The local vein-quartz was reduced by direct percussion and sometimes by bipolar technique. The small number of flake scars (three to four) on the cores indicates a low rate of flake production. Several kinds of platforms were present on the cores, including single-, double- and multi-platform cores. A few cores were discoids. As can be seen in Figure 5.4, the bipolar technique accounted for a high proportion of cores on grade A vein-quartz. In terms of the chaîne opératoire, after obtaining a nodule of raw material, the first step was the removal of most of the cortical surfaces by hammering, before proceeding with the bipolar technique if the raw material was of the right quality.

Figure 4.

The lithic industry of Longquan Cave. a) 1. Single platform core (LCMA2⑤:49); 2. Scraper (LCMA2④:10); 3. Scraper (LCMA2⑤:6); 4. Bipolar flake (LCMA2⑧:14); 5. Awl (LCMA2⑥:5); 6. Point (LCMA2③:13) 7. Drill (LCMC2⑭:2); 8. Discoidal core (LCMD2⑦:17). b) Heated stone (LCMA2⑤:42).

Figure 5.

1) Percentage distribution of the raw materials from zones A, C and D: Q1, 2 & 3: vein-quartz 1, 2 and 3; M: magmatic rock; S: sandstone; C: crystal. 2) Percentage of types of stone artefacts from zones A, C and D: CO: cores; FLA: flakes; IN-FLA: incomplete flakes. 3) Frequencies of core types from zones A, C and D: SIP: single-platform cores; DP: double-platform cores; SEP: multi-platform cores; DIS: discoidal cores; BIP: bipolar cores. 4) Comparison of raw materials of cores: Q1, 2 and 3: vein-quartz 1, 2 and 3; M: magmatic rock; S: sandstone; C: crystal.

Although most flakes have a nearly equal length and width, 30 have parallel sides and a length twice their width. These flake-blades have complicated dorsal ridges and no obvious regularity. The flint knappers appear to have taken advantage of longitudinal ridges purposely to produce flake-blades, but continuous reduction on one working face was limited.

Comments on the spatial distribution of lithics and bones

As seen in Figure 5.1, high-quality quartz is most common in zone A, and is outnumbered by inferior quartz items in zones B and C. Figures 5.2 and 5.3 demonstrate high frequencies of cores, hammers and anvils in zone D, but in zones A and C, flakes, brokenflakes and tools (scrapers, points, burins and so on) were common. The frequency of bipolar cores, discoidal cores and multi-platform cores is higher in zone D than in zones A and C. In addition, Figures 6.1 and 6.2 show that the size of flakes in each zone is almost the same, but large cores were scattered throughout zone D, in contrast to zones A and C.

From the above considerations, we believe that the functions of zones A, C and D were different. First, in the core-and-flake tradition, hammers were used to detach flakes and shape some of them into scrapers and points. The latter were used for procuring and/or processing resources. From this perspective, zones A and C, where there were many flakes and tools, are interpreted as activity areas, and zone D, where so many cores, hammers and stone anvils were found, was probably used as a refuse area. Second, as previously mentioned, in zones A and C, single-platform and double-platform cores were abundant, but bipolar, multi-platform and discoidal cores dominated in zone D. Furthermore, the cores in zones A and C were in the early stages of reduction, whereas most cores in zone D were in their final, exhausted stage, and discoidal, bipolar and multi-platform cores were dumped because they had lost the correct angle for knapping. It seems that when a core was too small for reduction and the raw material was of highquality, it was often reduced by bipolar technique so as to make better use of the raw material. Figure 5.4 indicates the relationship between bipolar cores and raw materials.

The largest cores, mostly of low-quality quartz, were most common in zone D, while in zones A and C there were more high-quality, vein-quartz items (Figure 5.1). This high-quality quartz was intensively used and then discarded, but low-quality vein-quartz collected near the site was not so fully exploited. People used this latter material to produce just a few flakes and then abandoned it, although the cores had more usable platforms than the higher-quality quartz. We therefore suggest that zones A and C were used for making and using stone tools, while zone D functioned mainly as a dumping area. In sum, the occupants of Longquan Cave obtained high-quality stone and produced as many flakes as possible before discarding the reduced cores, but obtained fewer flakes from low-quality raw material.

The faunal assemblage

Preliminary observations on the bones indicate that these too show significant differences between the three areas. Figure 6.3 shows fewer bones in zone C than elsewhere. The animal bones demonstrate different fragmentation patterns in zones A and D. In zone A bones are <150mm and mainly <100mm in length, but in zone D there are more bones longer than 150mm. This supports the interpretation that the spaces at the back of the cave were used for different purposes.

Figure 6.

Size distribution of cores, flakes and bone fragments.

A total of 460 animal bones, including 159 teeth, were identified (Table 5). They include 301 pieces of bones >30mm, all belonging to deer and buffalo. Of these, 63 pieces bear cut marks, and 10 pieces have rodent tooth marks. Weathering had affected 79 pieces severely and 44 pieces to a lesser degree; 109 fragments were burnt (32 seriously) and 3 pieces bear signs of abrasion. The many bones gnawed by rodents indicate that the main accumulation took place in the ‘discard’ zone at the back of the cave. The overall faunal spectrum reflects a forested environment of a slightly warmer time during Marine Isotope Stage 3 (MIS 3).

Table 5.

Measured values of taphonomic and archaeozoological variables from zones A, C, D and ‘others’, collected when the site was first investigated.

Unique bone tool

An elongated bone tool (specimen LCMD2⑤:46), found in spit 5, zone D, layer 2, was identified as an awl shaped from an ulna, probably of buffalo (Figures 7 & 8). It is 180mm long, 35mm across at its maximum width, 4mm at the widest part of its point and weighs 43.3g. Analysis conducted with the assistance of the late A.J. Legge allows us to present the object as well as the microscopic images.

Figure 7.

Four views of the bone tool.

Figure 8.

Detailed microscopic analysis of the bone tool.

Figure 7 shows the entire object; Figure 8 shows the piece under an optical microscope. In Figure 8.1 the area marked by an upper oval shape had been polished, but it was subsequently gnawed by a rodent. Figure 8.2 shows the detail of this portion of the bone tool with a number of parallel traces that are probably rodent tooth marks. The traces shown in rectangles indicate that the objects were formed by cutting and scraping with a stone tool. From the traces that modified the surface, the manufacturing process was reconstructed as follows:

1. 1) Obtain a buffalo ulna. The ulna is long and thin, and its medullary cavity is small and narrow, which is not an ideal choice as a source of marrow but makes it suitable for making bone artefacts because of its hard and robust texture.

2. 2) Shape the ulna by cutting a few centimetres from the proximal end along the lateral side of the bone and split into both the medial and lateral sides at the fracture. In order to keep the lateral and remove the medial, cut from medial to lateral again, about 80mm from the proximal end where the ulna becomes thinner. The cut is not vertical along the axis but is oblique, leaving a cut mark 47mm long.

3. 3) Shape the pointed distal portion by scraping and polishing. The modification follows the natural tapering of the ulna in its medial section while the lateral side (that which faces the outer side of the body) is smooth and hard. The effects of polishing are visible under the microscope. The tip of the point was probably damaged and was not found.

On the whole, one side of the bone awl remained in its unworked initial state and tapers naturally from the middle to the tip. The other side displays cut marks indicating that the bone was an ulna that had deliberately been made into a tool. On this face, there are distinct traces of honing, suggesting that the bone awl was tapered to a point. The pointed portion of the bone awl bears many marks along the vertical axis, presumably formed during taphonomic processes.