A while ago I posted a question to ask if folks had a list of brick
codes.  I do *not* mean set numbers, the number on the outside of the
cardboard box, when you buy a LEGO set in a store.  I mean the 4-digit
brick code seen on many bricks, and seen on almost all bricks from
modern moulds.
The brick code is usually found on the under side of the brick.  You
may have to tilt the brick back an forth in a bright light to catch
sight of it.  For example: under a humble 2x2 brick, picked up at
random, I find the numbers
	114
	3003
	7
When I pick up more 2x2 bricks, the "114" numbers change greatly, and
the "7" numbers also, but the 3003 is there on every 2x2 on the table.
I assume the "114" and "7" are batch numbers (probably of the mould,
not the brick).  Other bricks usually sport the batch numbers, too;
often in the form 7-114, sometimes using a structural element, rather
than the hyphen.  It is interesting to note that where there is room
for only one set of numbers, the batch number is given, rather than the
brick code; indicating quite a dedication to quality control (to me,
anyway).
When hunting for a brick code, I often find it is necessary to go
through single every one of my bricks of a given shape to find the cod;
it seems that the newer the brick, the more likely the presence of a
brick code.
The reson I want to find brick codes is to facilitate description.
Using a code which may be found on the bricks themselves seems a very
suitable way of describing them.  It also opens the possibility of
getting an "official" list from LEGO.
Note that there is zero correlation between the set numbers and the
brick codes.  For example, the "spare parts" set
	821 brick separator
contains one item, which sports a brick code of 6007.  There are many
set numbers which are the same as brick codes, and the two have nothing
in common.
Here is a list of brick codes compiled from a few hours of turning
bricks over and squinting carefully.  I would be greatly interested in
any additions or corrections.  There are some notable absences.
Note on notation:
	MxN	full height brick, M studs long, N studs wide
	MzN	1/3 height brick, M studs long, N studs wide
	MtN	1/3 height brick, M studs long, N studs wide, flat top
	MfN	1/6 height plate, M studs long, N studs wide, no under side
Code	Description
----	-------------
2336	6x2x2 approx, space chassis
2340	aeroplane tail fin, approx 5x1x3, base 4z1, top 2t1, offset 1 from base
2342	2z1 approx, ice planet control stick, wierd shape
2352	4x2x3 approx, window, sloped, 4x1 at top
2397	8x2 approx, auto acessory "side rails" (also used in space kits)
2415	2z2 approx, aeroplane wheel, single
2418	6x6x2 approx, space window, with 45 deg 2x2 trimming
2419	6z3 approx, with diagonal corners
2420	2z2 approx, L shaped
2431	4f1
2432	2z1 approx, auto acessory "roll bar"
2434	space block, 4x4x2, studs on long sides
2436	bracket, top 4t4, side 2z1
2437	4x3 approx, window, blue tint
2441	8x4 approx, auto chassis
2445	12z2
2452	2z1 approx, hinge piece, 3 prongs from long side
2456	6x2
2460	2z2 axel, points upwards, for heilcopters
2479	helicopter rotor, connects to 2460
2483	window (helicopter), approx 5x4x4.3
2484	2z2 axel block, with springs, big wheels (from "dune buggy")
2513	front wheel arch, like 4x3 tile
2540	auto acessory, bullbar, approx 2z1
2555	1z1 "grip"
2625	7z6 approx, fit atop 2626
2626	6x6 approx, boat bow
2873	hinge piece, approx 4t2, sideways attachment
3001	4x2
3002	3x2
3003	3x1
3006	10x2
3020	4z2
3021	3z2
3022	2z2
3030	10z4
3034	8z2
3035	6z4
3070	1t1
3137	2x2 approx, axel
3185	4x1x2 fence
3462	3z2 approx, helicopter rotor and axel
3471	6x6x7 approx, tree, base 2x2 circular
3475	2z2 approx, aeroplane jet engine, side mounting
3633	4x1x1 fence, offset to one side
3700	2x1 technics beam, 1 transverse hole
3710	4z1
3730	2z2 approx, ball coupler female
3747	3x2 inverted tile
3795	6z2
3823	4x2x2 approx, window, blue tint
3832	10z2
3933L	approx 8z4, "wing" with 3z7 diag bite top left
3933R	approx 8z4, "wing" with 3z7 diag bite top right
3935L	approx 4z4, "wing" with 3x3 diag bite top left
3935R	approx 4z4, "wing" with 3x3 diag bite top right
3938	hinge, top of 2x1
3940	2x2x2 approx, space, 2z2 base, 2t2 top, circular, stepped column joining
3956	bracket, 2z2, 2z2
3958	6z6
4032	2z2 circular, with "+" hole
4079	2z2 approx, auto accessory, seat
4132	4x2x3 window
4180	4x2 approx, axel, permanent wheels
4202	12x4
4212	10x4x1 approx
4213	4x4 approx, hinge, sideways attachment
4275	2z1 approx, hinge, 3 prongs from short side
4276	2z1 approx, hinge, 2 prongs from short side
4288	tyre
4345	2x2x2 approx, "cupboard" with door
4477	10z1
4588	1x1 approx, circular, with fins (rockets, etc)
4591	2x2x2 approx, circular, with fins (rockets, etc)
4596	4z2 approx, space, attachment is 2z1 to point with 1z1 female
4598	bracket, base 3z2 approx, side 2z2 approx
4600	2z2 approx, axel
4617	propeller
4623	2z1 approx, auto acessory, spike from side turns upwards
4625	4z1 approx, hinge, upwards attachment
4715	auto trailer wheels, connects to 2 of 4276
4727	1x1 approx, flower leaves, circluar
4728	1x1 approx, flower petals, circular
4730	2x2 technics (?), with axel (male) for propellers etc
4732	8x1.3 approx, auto chassis
4744	4x2x2 approx, rounded ends, only 2x2 attachment at top
4857	4x4x1 approx, "roof", joins hinge 4625
4859	4z3 approx, but with only 2z2 attachable
4864	2x1x2 only 1 wall down long side
4865	2x1 approx, auto acessory, only 1 wall down long side, no top studs (used in sets a fake door)
6007	brick separator
6014	wheel
6015	tyre for 6014
6069	4x4x1 approx, boat cowling
6075	10z2 approx, surf board (from "dune buggy")
-- 
Peter Miller   UUCP     uunet!munnari!bmr.gov.au!pmiller
/\/\*          Internet pmi...@bmr.gov.au
Disclaimer:  The views expressed here are personal and do not necessarily
        reflect the view of my employer or the views of my colleagues.
Interesting - I've saved the list and will (eventually) see if I
can add anything to it.
-- 
..Peter Murray           (opinions[my]!=opinions[organisation])
Wobbler thought that California was where good people went when they died.
        -- (Terry Pratchett, Only You Can Save Mankind)
-- Still definitely English and in England, whatever my address says. --
I assume you're talking about a list of set numbers and NOT a
list of brick codes.  The subject line says vice-versa.  I'm
freaking out over the prospect of seeing the list of bricks
someone mentioned in a previous post.  Did someone actually
post it and it never reached my site?  Ay caramba! 
Thanks for filling me in.  I don't know how I missed the
original post.  After work I'll see what I can add to the list.
(Not that I really care. I just can't avoid commenting upon things
 like this. It's probably a brain-damage coming from too much
 proof-reading. Sorry.)
Stefan
3x1 bricks come in white, black, grey, blue and red at least. Also they come
in flats in a range of colours. 
			      -- the SillyWiz --
  -------------------------------------+--------------------------------------
The University of Warwick cares little | "Don't worry, there's absolutely no
for my opinions the rest of the time so| way they can hit us from all they
it can't have these if it wants them.  | way over th.."
  -------------------------------------+--------------------------------------
     Keith Lucas ---- sill...@dcs.warwick.ac.uk , cs...@csv.warwick.ac.uk
  ----------------------------------------------------------------------------
 Argh, this site has done it again. What? You don't know what happens
every now and then? Well, let me tell you, this pig of a system goes
and expires all the articles without me having read them all.
 You obviously have never seen The Yellow Castle (it is so great I
just have to spell it big). It has lots of them, as do the old style
space sets.
>(Not that I really care. I just can't avoid commenting upon things
> like this. It's probably a brain-damage coming from too much
> proof-reading. Sorry.)
 You'll enjoy the net proof-reading, so many people and so few
actually reading what they write themselves.
--
>Is your example with the code 3003 for 2x2 bricks authentic?
>In your list, you list 3003 as the code of a _3x1_ brick.
>I can't recall ever having seen such a brick. A typing error,
>perhaps?
Uh-Uh. I have several of these - only about 2 actaully - both black and
were from the original Technic Go-Kart.
> Stefan
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