embodiments of the invention will be described in greater detail below with exemplary materials being given for some specific or individual elements of the device . in addition the exact material or surface decoration of an element can be changed . the embodiment illustrated in fig1 is a communication device 1 with a hallmarked casing 2 . the casing 2 of the device has been designed to be recyclable as the requisite metal elements are 22 carat gold . the casing 2 has an optically permeable front face 3 providing a display region 4 and an input region 5 that includes a key array 6 . the key array 6 includes a first group of alphanumeric keys 7 , for entering telephone numbers , writing text messages ( sms ), writing names ( associated with phone numbers ), etc . each of the twelve alphanumeric keys 7 is provided with a figure “ 0 - 9 ” or a sign “#” or “*” respectively . in an alpha mode each key is associated with a number of letters and special signs used in text editing . the key array 6 additionally comprises two soft keys 8 , 9 , two call handling keys 10 , 11 , two scroll keys 12 , an on / off key 13 and a dedicated key 104 . the functionality of the soft keys 8 , 9 may depend on the state of the communication device and position within the menu accessed using the scroll keys 12 . the current functionality of the soft keys 8 , 9 can be shown in separate fields in the display region 4 just above the respective keys 8 , 9 . the two call handling keys 10 , 11 are used for establishing a call or a conference call , terminating a call or rejecting an incoming call . the two direction keys or scroll keys 12 , in the handset illustrated are placed centrally on the front surface of the communication device between the display region 4 and the group of alphanumeric keys 7 perform a scrolling function . the front face 3 is overlaid with a pillow 16 providing apertures 17 to channel sound from a loud speaker 18 and providing an appropriate feel for an element of the device that will be located close to the user &# 39 ; s ear . the front face 3 is surrounded by a bezel 19 that is made 22 carat gold . the choice of material for the bezel is one open to selection . precious metals including gold , platinum , silver , steel amongst others would be suitable . the same applies to the material of the front face protectors . although for the maximum benefit of the present invention all the metal elements would be formed from the same precious metal . this acts to protect the edges of the front face 3 and can help in some embodiments in securing the elements of the casing 2 together . the casing 2 is formed from the front face 3 surrounded by the bezel 19 , a side frame 20 and a back cover 21 . the interface between the side frame 20 and the bezel 19 and the side frame 20 and the rear cover 21 are shielded by rails 22 , 23 in this embodiment . the rails 22 , 23 hide raw edges from view , and strengthen the casing . the construction of the casing 2 enables it to be opened with ease and broken down into its constituent parts for recycling . the device will now be briefly discussed with reference to its functional elements . the communication device 1 , includes the key array 6 , a display 25 , an antenna 26 , an ear piece speaker 18 , a polyphonic speaker 27 , and a microphone 28 . the communication device 1 is adapted for communication via a wireless telecommunication network , e . g . a wireless network . however , the communication device could also have been designed for a cordless network . fig3 shows schematically and functionally elements of the communication device 1 . the microphone 28 records the user &# 39 ; s speech , and the analogue signals formed thereby are a / d converted by an a / d converter before the speech is encoded in an audio part 29 . the encoded speech signal is transferred to processor 30 . the processor 30 may support software in the phone . the processor 30 also forms the interface to peripheral units of the apparatus . these may include a random access memory ( ram ) 31 and a flash read only memory ( rom ) 32 , a sim card 33 , the display 25 , and the key array 6 , and perhaps a browser application 34 , and a location module 35 . the browser application 34 can be used to request and receive information from the internet . the location module 35 enables the terminal 1 to determine its current position . the processor 30 communicates with a transceiver 36 , e . g . a circuit , which is adapted to send and receive messages in a telecommunication network . the telecommunications network may be a gsm or w - cdma network , but the invention may also be applied in connection with any other network , including but not limited to other kinds of wireless networks and various forms of cordless phone systems or in dual band phones accessing sets of these systems or networks . the audio part 29 speech - decodes the signal , which is transferred from the processor 30 to the earpiece 18 via a d / a converter . the ‘ engine ’ providing the electronic function of the device does not form part of the casing and as there are particular requirements for the materials used in providing the function is given special dispensation to not be 22 carat gold . this extends to the subframe defining the battery compartment and sim card holder which is made from stainless steel . in the illustrated embodiment the edges of the front face 3 is protected by the bezel 19 that sits around the whole of the face . the bezel 19 , in this embodiment , is formed from solid gold of the same purity as the other gold elements in the device . the solid metal bezel made from the same precious material allows the device to be hallmarked to that gold purity level . as can be seen in fig1 , the bezel 19 is punctuated with front face protectors 63 whose function will be described in more detail later . these front face protectors 63 are also made from the same carat gold , and in this particular embodiment play a role in holding the casing elements together . the front face protectors 63 have a tip part 64 that extends over the bezel 19 and a shaft 65 that passes through the bezel 19 and into the plastic side frame 20 . both these parts are made of the same grade precious metal used for the other metal parts of the casing . the shaft 65 may be tightened onto the frame 20 using a nut 95 which is formed from stainless steel . this is allowable as the connection is mechanical , it is not visible and provides a better functional connection . in this case the nut stops the front face protectors from falling out of the device . in one embodiment the shafts 65 are screwed into the tips 64 at one end and into the side frame element 20 at the other although other manners of connection could be employed . the shaft 65 and tip 64 could also be one piece rather than two . the bezel 19 and the transparent face 3 are captured by the front face protector 63 and side frame element 20 as can be seen in fig7 b . the front face protectors 63 accordingly grip the transparent face 3 securely between the side frame 20 and the bezel 19 . the front face protectors 63 are only located next to the key array 6 . in order to secure the transparent face 3 around its perimeter additional stainless steel screws are added to draw the bezel 19 towards the side frame 20 and squeeze the transparent face 3 in place . in one embodiment , the screws thread through the side frame 20 and tap into the bezel 19 . these screws are not formed from the precious metal as the characteristics are not so suited to their function as the stainless steel . as can be seen in fig7 , a first rail 22 is located in the interface between the side frame element 20 and the front face 3 . the rail 22 hides the discontinuity between the parts from sight and protects vulnerable edges to enhance the durability of the device 1 . the rail 22 may be a stamped metal piece extending around the perimeter of the side frame 20 . the stamped piece 68 is trapped between the side frame member 20 and the bezel 19 as these two pieces are drawn together on assembly . the stamped piece has apertures 70 that sit over corresponding projections 71 on the side frame 20 member to prevent it from being withdrawn from between the two parts when in position . the stamped piece acts as a carrier plate to which an additional extruded piece 72 is soldered to provide a seamless finish . the stamped piece 68 and the extruded piece 72 and any solder is of the same precious metal , in this embodiment , gold as the bezel and other metal parts . for this and other connections described in the specification , laser welding is an option . the solder is of the fineness necessary to allow the article to be hallmarked 22 carat gold under the vienna convention . the side frame member 20 in this particular embodiment is a plastic support 73 with an exterior cover 74 . the cover 74 may be a wood veneer or another layer such as leather or other skin provided it is not metal . the bonding agent most suitable for adhering the layer to the plastic frame member 73 will differ depending upon the materials that need to be adhered . similarly the back cover 21 in this embodiment may have a plastic frame and be covered with for example a leather or wood veneer . with the flexible veneer materials such as leather , it is preferable for the material to be taut on the frame . this is achieved during the veneering process using conventional techniques . the constructed casing 2 provides a housing for the printed circuit board 50 holding the engine components , and a battery 79 . when the device 1 is a radio telephone , the casing 2 may also provide a sim card holder 80 to accommodate a sim card . for operation under some radio protocols this will clearly not be necessary . returning briefly to the front of the device , located above the display region 4 is the pillow 16 so named because it designed for the user to rest his or her ear against when making a telephone call . the pillow 16 overlays the ear piece 18 of the device . the pillow 16 provides suitable apertures 17 to channel sound to the user . the material of the pillow 16 can be chosen to be a material that is inherently warm to the touch . materials that are thought to be particularly suitable are wood and leather veneers . the shape of the pillow 16 obscures part of the lcd 25 , providing opposing triangular sections 82 , 83 that are used to indicate battery capacity and signal strength respectively . to complete the structure , the casing 2 has a rear cover 21 and internal compartments 84 , 85 suitable for retaining the engine 24 the battery 79 and in this embodiment a sim card . the device illustrated , in common with many other radio telephones , advantageously allows access to the battery compartment 85 as the battery 79 may periodically need replacement . in order for the engine to be protected during this activity , the battery 79 is retained in a compartment providing connectors to the engine . alongside the battery compartment 85 in this embodiment is the sim card holder 80 . under protocols where a sim card is used to hold subscription information , the user may wish to remove the sim card . the battery compartment 85 and sim card holder 80 are provided by an internal casing element 87 that is secured to the side frame 20 . this may be formed from plastic or one of many other suitable materials . in one embodiment the compartments are formed from stamped metal sheet . the metal is preferably stainless steel for its properties , and has special dispensation as it is considered to be part of the ‘ engine ’ and is not visible to the purchaser . the casing 2 is completed by assembling the back cover 21 to the side frame 20 . in the illustrated embodiment , the back cover 21 is formed from three pieces 96 , 97 , 98 . a first piece 96 overlays the antenna location . a second piece 98 covers the speaker and a third piece 97 , the battery compartment . the back cover 21 may be made from ceramics which are clearly distinguishable from the precious metal parts . with ceramics , however , despite having many desirable characteristics , for locations near an antenna relevant for devices containing such an element , the dielectric constant of the material interferes with the desired transmission pattern . to provide many of their desirable characteristics without the dielectric constant becoming too high , the first piece 96 can be formed from a material with a lower dielectric constant with a suitable depth of layer deposited on it . the rear casing element 96 covering the antenna is attached to frame element 20 and in the process captures the second rail 23 similar in construction to the first rail 22 between the side frame 20 and the back cover 21 . again the rail 23 is provided with apertures 70 that are positioned over corresponding projections 71 on the side frame 20 to more securely hold the rail 23 in position when the back cover 21 is attached . the second rear casing element 98 is attached to the side frame 20 in a similar manner to that described in relation to the first rear casing element . the second rear casing element 98 is formed from the same precious 22 carat gold as the other metal parts and covers the polyphonic speaker 27 . it is provided with a suitable aperture 102 to channel sound from the polyphonic speaker 27 that may be used in hands free mode and for providing an audible ring tone . this additional speaker 27 has not been optimised for use in close proximity to the ear as has the speaker 18 located beneath the pillow 16 . this allows it to be more effective as a handsfree speaker and enables a greater range of ring tones to be utilised . a third rear casing element 97 covers the battery compartment 85 and the sim card holder 80 . this element is releasably secured to the other casing elements using screws 99 to allow relatively easy access to the sim card and battery 79 . the battery cover 97 is formed from a ceramic cover with a titanium battery cover support . the titanium is allowed as the material needs to be rigid and is not visible . in a preferred embodiment a quarter turn of a screw 100 releases the cover element 97 to allow it to be removed . the same action can disconnect the battery 79 to allow the sim card to be removed . the input region 5 comprises a key array 6 , as described above . in this embodiment , the key array is made up of a plurality of individual keys 7 - 13 . each of these individual keys comprises a key 164 and shaft 49 extending from substantially the centre of the key 164 . the keys 164 are formed from the same precious metal . in this embodiment 22 carat gold . the keys 164 are crafted into the desired shape from the same precious metal , in this embodiment , gold . the key shafts 49 are , however , stainless steel as they need to be strong and intricately turned . the key shafts are screwed into the keys so they are easily removed for separate disposal . individual keys such as dedicated key 104 are also formed from gold . however , these are attached to an elastomer undermat for water sealing . as the gold should be extractable from the casing without retaining residues , the gold is not adhered to the elastomer undermat , instead a mechanical connection is created . a protrusion 107 on the gold key having an enlarged tip 108 is forced through an aperture 109 in the elastomer undermat to hold the key firmly attached to the casing . other single keys such as the power key are attached to the casing in a similar fashion . the metal surround 110 of this and other single keys are also formed from solid gold , crimped into the aperture in the support frame 20 . by crimping , resistant fitting and soldering using suitable purity of precious solder , the precious elements of the casing can be conveniently dismantled while retaining the required purity levels . where appropriate laser welding can also be used . by forming all the metal parts other than those with incompatible functional requirements from 22 carat gold the whole article can be hallmarked ensuring the owner has confidence that the metal parts are all of the same purity . although the device has been described with metal parts being formed from 22 carat gold . other precious metals could be substituted to meet recognised hallmarking criteria , or with different purity levels should that be desirable . as mentioned in the introductory portion , silver and platinum are candidates as well as both white and yellow gold of same fineness . in particular the fineness to meet the different levels of purity set out in the vienna convention . in other embodiments the metal parts could be formed from other recyclable metals such as steel , tin etc . aspects of the invention have been discussed with reference to a radio telephone function . it will be clear to the skilled man that these aspects apply equally to other portable communications devices supporting in addition or as an alternative other functions , such as , amongst others electronic diaries , and electronic notepads . the skilled man will be aware that the materials described above in relation to specific elements of the device can be mixed and matched to suit many distinct design options . the present invention includes any novel feature or combination of features disclosed herein either explicitly or any generalisation thereof irrespective of whether or not it relates to the claimed invention or mitigates any or all of the problems addressed . in view of the foregoing description it will be evident to a person skilled in the art that various modifications may be made within the scope of the invention .