Table 8 Calorific, lux and radiative heat values for the different wood species. The lux and radiative heat values were combined using data in Tables 5, 6 and 7 and then averaged

From: Assessing the Function of Palaeolithic Hearths: Experiments on Intensity of Luminosity and Radiative Heat Outputs from Different Fuel Sources

Fuel type Species Calorific value Radiative heat Lux
Fresh bone Roe Deer (Capreolus capreolus) NA 23.5 5.7
Softwood Spruce (Picea abies) 17.82 39.9 29.5
Softwood Alder (Alnus glutinosa) 18.27 19.8 10.5
Softwood Pine (Pinus sylvestris) 17.62 37 24.65
Softwood Larch (Larix decidua) 17.81 36.5 29.05
Hardwood Oak (Quercus robur) 17.58 30.35 6.35
Hardwood Beech (Fagus sylvatica) 17.7 31.5 29.05
Hardwood Ash (Fraxinus excelsior) 18.05 50.5 66
Hardwood Silver Birch (Betula pendula) 18.13 50.5 56