Contents:

1. Date codes
2. Nib codes
3. Hallmarks and other markings
4. Condition codes
5. Abbreviation codes

1. Date codes on Parker Pens

In mid 1934 Parker began marking most pens and pencils with a date code, both the barrel and the nibs were marked, but lacking a date code doesn't necessarily mean that the pen was made pre-1935, since many imprints have been worn off with use. The first date codes, found for example on the Vacumatics, consists of two digits, the first one denoting the quarter of production, the second denoting the production year. Hence a "47" marking on a 1930's pen indicate that the pen was produced in the fourth quarter of 1937, not 1947, which is a common misconception.

In the second quarter of 1938 this system was however changed to save production time, and a new date code, using a system of dots, was adopted. The stamp initially had three dots and for each quarter one dot was filed down leaving none for the fourth quarter. Since production was overlapping examples exist with either the imprint 28 or .8. for the the second quarter of 1938. Also, since this coding system extended over a decade, a pen marked 38 could be produced the third quarter either in 1938 or 1948.

In 1950 a new system for the date coding was introduced where the two digits only indicated the year, not the quarter hence "50" means made in 1950, this system was used in the US until 1955 and in Canada a few years longer..

It has been assumed that Parker began marking some of their pens on the trim or cap bands to allow for dating in 1970. Using the words "Quality pen", one letter per year, followed by a quarter marker, allowing for dating within a ten year span.
So far the earliest date coded pens found have had the code NL for 1979, and all of these pens were made in the US. Possibly anticipating the 1980 official start of date coding in France and the UK, this could have led to the presumption that the dating actually began in 1970, but proof of this has still to be found.
The quarter marker changed in 1988 from E,C,L,I to III,II,I or none (last quarter) according to the below table.
In 2000 the code again underwent a small change when the quarter switched sides with the year and there was a dot between them "Q.III"
There are however inconsistencies, such as missing dots and quarter codes appearing on the wrong side of the year code.

Year Q1 Q2 Q3 Q4
---------------------------------
1979 - -- -- NL NI Date coding begins in the US

1980 - QE QC QL QI Date coding begins in the UK and France
1981 - UE UC UL UI
1982 - AE AC AL AI
1983 - LE LC LL LI
1984 - IE IC IL II
1985 - TE TC TL TI
1986 - YE YC YL YI

1987 - PE PC PL PI
1988 - IIIE IIE IE E (change)
1989 - IIIN IIN IN N

1990 - IIIQ IIQ IQ Q
1991 - IIIU IIU IU U
1992 - IIIA IIA IA A
1993 - IIIL IIL IL L
1994 - IIII III II I
1995 - IIIT IIT IT T
1996 - IIIY IIY IY Y

1997 - IIIP IIP IP P
1998 - IIIE IIE IE E
1999 - IIIN IIN IN N

2000 - Q.III Q.II Q.I Q (change)
2001 - U.III U.II U.I U
2002 - A.III A.II A.I A
2003 - L.III L.II L.I L
2004 - I.III I.II I.I I
2005 - T.III T.II T.I T
2006 - Y.III Y.II Y.I Y

2007 - P.III P.II P.I P
2008 - E.III E.II E.I E
2009 - N.III N.II N.I N

2. Nib codes

(there are discrepancies between models)

62 Accountant-Produces very thin lines with a delicate touch.
Generally used for figure work 14k

63 Extra Fine-For fine line writing with a light touch 14k

64 Steno-A fine point adapted for use in shorthand and speedwriting 14k

65 Fine-Excellent for general writing and note taking. Moderate
pressure produced a fine line 14k

66 Medium-Best for average writing pressure, average line width,
general all-around use 14k

67 Broad-A heavier, rounded point for wide lines 14k

68 Extra Broad-A large rounded point. Excellent for heavy lines and
bold signatures 14k

69 Fine Stub-A flat point for delicate shaded writing and printing.
Produces heavy lines on horizontal stroke, thin lines on vertical
stroke 14k

70 Medium Stub-a heavier flat point for shaded writing and printing.
Designed for people who hold the pen with very little slant 14k

71

72 Extra Broad Stub-Parkers widest stub point. For very heavy
lines on the down stroke and medium lines on the side stroke 14k

73

74 Fine Oblique Italic right hand 18k

75 Medium Right Oblique 14k

75 Medium Oblique Italic right hand 18k

76 Broad Oblique Italic right hand 18k

77 Fine Oblique Italic left hand 18k

78 Medium Oblique Italic left hand 18k

79 Broad Oblique Italic left hand 18k

79 Medium Left Oblique-For those who slant the pen when they write. Right Oblique has the largest surface on right sided of point. Left Oblique has opposite slant for left handed writers 14k

80 Needle Point 18k
81
82
83
84
85 Extra Broad 18k
86 Extra Extra Broad 18k
87 Fine Oblique right hand 18k
88 Medium Oblique right hand 18k
88 Extra Broad Executive-Developed for people who like to write boldly and rapidly and want a special flourish to their signatures 14k

89 Broad Oblique right hand 18k
90
91 Extra Broad Oblique right hand 18k
92 Extra Extra Broad Oblique right hand 18k
93 Medium Oblique left hand 18k
94 Medium Italic 14k
95 Broad Italic 14k
96 Fine Oblique left hand 18k

97 Fine Italic 14k
97 Broad Oblique left hand 18k

98 Fine Italic 14k
98 Heavy Italic-Expressly designed for italic handwriting. Flat, broad edged points generally put to paper at a 45 degree angle 14k

Also
X Extra Fine
F Fine
M Medium
B Broad

FI Fine Calligraphic
MI Medium Calligraphic
BI Broad Calligraphic

3. Hallmarks and other markings

Parker, Maker's Mark:

Parker Pen company, USA

Parker Pens. ltd, UK

Parker Pen, France

Parker Pen Company, Canada
PPCO

Solid Gold (K or CT for Karat/Carat)

24K or 1000 (parts of 1000)
22K or 916
18K or 750 lowest allowed gold content in France until 1994
15K or 625 discontinued in 1935
14K or 585
12K or 500
10K or 416 Lowest allowed gold content in USA
9K or 375 Lowest allowed gold content in Canada and UK
8K or 333 Lowest allowed gold content in Germany

Common Parker markings:
375
585
750
9K
14K
18K

Gold filled or Overlay:
A solid layer of gold, mechanically bonded to brass, or sometimes other materials, with heat and pressure. Usually about 80-120 micrometer thick. One micrometer is 1/1000 of a millimeter. (ca. 0.000039 inches)
To be stamped 10K the layer must equal at least 1/10 of the total weight of the item.
To be stamped 12K or higher the layer must equal at least 1/20 the total weight of the item.

Common Parker markings:
1/10 12K Gold Filled
14K GF
1/8 14K Gold Filled
1/10 14K Gold Filled
1/10 16K Gold Filled

Rolled Gold:
Same process as the above, but the gold sheet is rolled down after the bonding, which produces a thinner layer of gold, usually 20-40 micrometer thick.

Common Parker markings:
Rolled Gold
1/10 12ct R Gold

Gold plated:
Gold plating is usually a thinner layer than the above. Electroplating chemically adds a very thin layer of gold to the base material. Much more prone to brassing. Usually less than 10-20 micrometer thick.

Gilded:
Same process as abouve but a very thin layer of gold, usually less than 5 micrometer thick.

PVD aka Dimonite G aka Fileté:
In 1986 Parker patented a process, developed together with Jamers Snyder of the University of Wisconsin, for depositing microlayers of gold and titanium nitride to create the glow of gold but the durability of chromium. The process involves physical vapor deposition of gold (PVD). Parker called it "Dimonite G". According to Parker a microlaminated surface of 1.3 micrometer has a "service life" equivalent or exceeding that of a 10 micrometer gold plating. And since the gold part of the microlayer can be as thin as about 0.003–0.3 micrometer, the amount of gold used in the  process is incredibly low. But to reach a 93% visual accuracy compared to traditional gold plating, Parker uses a 3 micrometer layer of which 0.4 micrometer is 14K gold.

USA Solid Gold

24K
22K
18K
14K
12K
10K

USA Silver

925 (Sterling)
900 (Coin)

Common Parker markings:
Sterling Silver

France Solid Gold

Seahorse, 24K gold

Eagle, 22K gold

Eagle, 18K gold

Shell, 14K gold

Clover, 9K gold

Standard, below 9K gold, foreign

Foreign or unknown

France Silver

Silver 999 (of 1 000) Fine

Silver 925 Sterling

Silver 800

Silver Standard, below 800

4-Condition-code standard for writing equiptment

This is a standard for shortening the description of pens, either for personal use or when offering pens for sale. The code-key could be posted along with the pen-list, if desired.
The following codes should be used to establish an overall condition, rather than be taken literally. Flaws should always be noted, such as scratches, cracks, dents, etc.

PM = Pristine Mint. Untouched, unfilled. No marks or spots whatsoever. Crisp colour. Never filled. This condition rarely exists. Absolute perfect condition.

M = Mint. Perfect condition. No marks, spots or brassing. Crisp colour and shiny finish on plastic pens. No discolouration. Working condition. These pens can be filled. Not filled pens should be noted. NOS pens should be in Mint condition.

NM = Near Mint. An excellent pen, but with parts of duller finish or nearly invisible surface scratches. No brassing, virtually a Mint pen, but with small signs of usage.

VF or EX = Very Fine or Excellent. Visible, but not accented surface scratches or parts of dull finish. More accented scratches where the cap goes on the butt and body. Otherwise fully functional and crisp finish with no brassing.

FN = Fine. Visible surface scratches or dull finish. Signs of wear on the nib or light discolouration of the section or around filling lever or button filler. Light brassing or small lip crack. Clear signs of usage, but still a better than average pen.

VG = Very Good. Some scratches and dull finish. Signs of everyday usage on nib or body. Brassing, light all over discolouration. Minute lip or body cracks. Loose cap rings or body rings. A used pen in average condition.

G = Good. Scratches, dull finish. Nib and body well used. Brassing, discolouration. Small lip or body cracks. Light cap or blind-cap misfit. Loose cap rings or body rings. Worse than average condition, but still a fully functional pen.

F = Fair. Severe scratches and marks. Severe brassing. Discolouration. Small lip or body cracks. Cap or blind-cap misfit. Loose cap or body rings. Still functional, or functional with light attention.

P = Poor. Severe scratches and marks. Svere brassing and discolouration. Severe cracks or essential parts missing. Cap, bodyrings or lever missing or loose. A not functional parts pen.

5. Abbreviations:
BC = Blind cap
BCHR = Black, chased hard rubber
BHR = Black hard rubber
BLHR = Black lined hard rubber
BY = Body/barrel
CF = Capillary filler
CL = Clip
CP = Cap
CPT = Crome plated trim
CS = Clip screw
EB-1 = Engraved body/barrel. Light and small
EB-2 = Engraved body/barrel. Light or small
EB-3 = Engraved body/barrel. Deep or large
EB-4 = Engraved body/barrel. Deep and large
EC-1>4 = Engraved cap. Ditto.
ED = Eyedropper filled
FU = Filler unit
GF = Gold filled
GFF = Gold filled filigree
GFM = Gold filled mounted
GFT = Gold filled trim
IF = Ink feed
IM = Iridium
LF = Lever filler
MBL = Marble
MHR = Red and black mottled hard rubber
MIB = Mint in box
NB = Nib
NF = Never filled.
NOS = New Old Stock. Untouched, unfilled pens, not currently available in stores.
NPT = Nickel plated trim
NS = Needs sac
PF = Plunger fill
PR = Plunger
RBHR = Red and black hard rubber
RCHR = Red chased hard rubber
RG = Rolled gold
RHR = Red hard rubber
RRHR = Red-ripple hard rubber,
RT = Ring top
SGM = Solid gold mounted
SF = Silver filagree
SFD = Silver filled
SGF = Solid gold filagree
SN = Section
SPT = Silver plated trim
SSM = Solid silver mounted
TD = Touchdown filler
TR = Tassie ring
VM = Vermeille