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Study of Gross Features

Before resorting to any kind of aid, it is advisable to study the gross features of the timbers which are visible to the naked eyes, as a great deal of helpful identification guide can be obtained in this manner.

  • SAPWOOD AND HEARTWOOD

    The difference between sapwood and heartwood can also be diagnostic importance. In some timbers, there is a distinct change between sapwood and heartwood whereas in others there is no distinction between them.


  • RESIN CANALS

    The Resin Canals can often be seen with the naked eyes on the longitudinal surfaces (tangential and radial surfaces) of Dipterocarpaceae species e.g. Dark Red Meranti, Selangan Batu, Selangan/Merawan, Selangan Merah, Giam etc.


  • COLOURS

    Some people rely to a great extent on colour as a guide to the identification to certain timbers, but in general, colour is not a very reliable feature. Colour can be variable at times and it is good to have a sample with both sapwood and heartwood in order to obtain a true colour. Use colour cautiously as far as timber identification is concerned, for it can often be misleading. Colour often changes with age, and the timber can have a totally different colour compared with the fresh sawn condition. Do not, however, disregard colour, but use it in conjunction with other features in final analysis.


  • TEXTURE

    We refer to texture as being coarse, medium or uneven, and fine. Those with large pores or vessels e.g. Keruing, are coarse in texture and those with small, compact elements have an even or fine texture.


  • ODOUR

    Many timbers have a distinctive odour, e.g. Kapur, have a camphor smell and and Keruing, having a very sharp peppery smell. In many cases, odour is fleeting, disappears with age. It can often be revived by cutting the end section or by rubbing and warming the specimen. And now a word of warning with regards to the use of odour as a means of identification; a piece of wood which has been in contact with another specimen, which having a powerful odour will inevitably pick up some of the odour, and this may prove to be mystifying and misleading.


  • WEIGHT

    With practice, it is possible to make a reasonable estimate of the weight of timber and, thus, you narrow your "guess" to that small group of "weight class".


  • HARDNESS

    A simple, rough and ready test for hardness can be made by observing if specimen readily indents or resists indentation with finger or thumbnail. Hard timber such as Belian or Selangan Batu will hardly show any marking at all. Medium weight timber such as Kapur can be slightly indented whilst light weight timber such as Jelutong indents easily and will show deep markings.


  • FEELING

    Feel warm, wet dry or oily.


  • SURFACE

    Lustrous or dull.


  • OTHER AIDS SUCH AS CHEMICAL OR BURNING TEST

    This is not important.


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