Chatoyance was measured by the chatometry.com team using the PZC method. The statistics for this specific timber are hereby summarized to provide an evaluation of data robustness:
Number of sources for samples: 6
Number of individual trees analyzed: 6
Number of specimens: 13
Number of measurements: 42
Max PZC read (of all measurements): 16.4
Min PZC read (of all measurements): 9.7
Max PZC average on one log: 15.0
Min PZC average on one log: 10.5
PZC Average of all logs: 12.8

Species: nauclea diderrichii
Family: Rubiaceae
Clade: Angiospermae
Description: Nauclea diderrichii, commonly known as Opepe or Kusia, is a large evergreen tree native to West and Central Africa. It grows up to 50 meters tall with a straight trunk, featuring glossy, ovate leaves, small creamy-white flowers in dense spherical heads, and fleshy, orange-red spherical fruits. It is highly valued for its durable, yellowish-brown timber.
Other Local Names: Aloma, Engolo, Opépé, Akondoc, Bonkingu, Badi, Kusia, Aloma, Opepe, Kilingi, Kilu, N’gulu-maza, Opepe, Bundui

Reference Colour: Orange yellow
Texture: Medium
Grain: Interlocked grain
Interlocked Grain: Marked
Notes: Wood is a perfect golden yellow or slightly moiré orangey yellow. In interior end-uses, the colour remains stable.

Diameter: 60÷90cm
Density @12% MC: 760kg/m³
Janka Hardness: 1590lbf
Crushing Strength @12%MC: 63MPa
Static Bending Strength @12%MC: 95MPa
Longitudinal Modulus of Elasticity E: 14.66GPa
Volumetric Shrinkage Coefficient: 0.55% per %
Total Tangential Shrinkage TS: 7.5%
Total Radial Shrinkage TS: 4.5%
T/R Anisotropy Ratio: 1.7-
Fibre Saturation Point: 25%
Thermal Conductivity: 0.25W/mk
Lower Heating Value: 19600KJ/Kg
Sapwood Thickness: 3÷5cm
Sapwood Demarcation: Clearly demarcated

Resistance to Decay: Class 1 – very durable
Resistance to Dry Wood Borers: Class D – durable (sapwood demarcated, risk limited to sapwood)
Resistance to Termites: Class D – durable
Treatability: Class 2 – moderately treatable.
Use Class Covered by Natural Durability: Class 4 – in ground or fresh water contact BILINGA / OPEPE*
Durability Notes: This species is listed in the NF EN 350 standard. Bilinga naturally covers the use class 5 (wood permanently or regularly submerged in salt water, sea water or brackish water). According to the European standard NF EN 335 of May 2013, performance length might be modified by conditions in which it is used.

Log Buoyancy: Does not float
Log Conservation: Good
Drying Rate: Slow
Drying Risk of Distortion: Slight risk
Drying Risk of Case Hardening: No known specific risk
Drying Risk of Checking: High risk

Blunting Effect: Normal
Sawing Tooth: Ordinary or alloy steel
Machining Tool: Ordinary
Suitability for Peeling: Bad
Suitability for Slicing: Good
Assembly Nailing Screwing: Good but pre-boring necessary
Assembly Notes: Wood presents slight tendency to split when nailing. Wood is acidic: to be taken into account when gluing.
Additional Notes: Risk of splitting in outdoor uses in dry, hot environments. Needs filling before, polishing. Resistant to one or several acids
End Uses: Heavy carpentry, Decking, Ship building (planking and deck), Bridges (parts in contact with water or, Cabinetry (high-end furniture) ground), Vehicle or container flooring, Bridges (parts not in contact with water, or ground), Panelling, Poles, Interior joinery, Exterior panelling, Built-in furniture or mobile item, Hydraulic works (seawater), Flooring, Sleepers, Industrial or heavy flooring, Sliced veneer

Source 1: Tropical Timber Atlas, Editions Quae, e-ISBN 978-2-7592-2770-9