There seems to be little knowledge (diplomatic speak for ignernce) on the various US & UK Jag forums in re JRG. Brighter metallic Jaguar Racing Green was developed circa 2000 AD as being more telegenic for the ill-fated Jaguar F1 adventure (Google Image: Jaguar F1). It was also an option on some street cars. I'd recently seen a classified adv. in a motoring magazine for a 2007 XK coupe in JRG. I hadn't known XK150s were available in that color/colour. (Not to be confused with metallic or enamel British Racing Green, Botanical Green or any other Jag dark green color. You're welcome)

 

With respect, the paint code for Jaguar Racing Green is HGZ (not JRG) - every green tone code in Jaguar's colour range begins with H.
In 2007 the XK colours included Jaguar Racing Green (HGZ), British Racing Green (HGD) and Emerald Fire (HHP) - the latter being very bright. It should be noted that not all colours were available in every market - but the colour codes remained stable.
The attached photo shows my 2007 XK in British Racing Green (HGD) - in shade it looks almost black. In any light it is gorgeous.

 

So, I don't know about the road car colours but I do happen to know about the F1 cars, I'm sure if you really want the colour codes I could find out. There were two different supplies of the paint for Jaguar F1, initially (and for quite some time) they were paying big money for the BRG (which had a nice gold flick in it) from ICI if memory serves me correctly, after a few years of being sponsored by Du-pont they realised they could probably get it for free! I'm not 100% on the original supplier though as I do think ICI may be part owned by Du-pont, like I said if you're really keen I can find out.

 

I've certainly met people who refer to JRG, BRG and so on, but having said that I believe the actual paint codes are as posted by sov211 above.

Mine's JRG, code HGZ.

(There's also a green-tinged silver, if I can call it that, which is Seafrost or some such name.)

 

A fine color for a fine machine!

 

[QUOTE=JagV8;1618590]I've certainly met people who refer to JRG, BRG and so on, but having said that I believe the actual paint codes are as posted by sov211 above. (End of quote)

When people refer to British Racing Green as "BRG" or Jaguar Racing Green as "JRG" they are simply "short-forming". You cannot order the paints by these acronyms. And there are various tones that fit the acronym of "BRG". Jaguar has had several formulations of Jaguar Racing Green over the years, but each one had a different three-letter code.
To repeat, all green-based colours in the Jaguar colour range have the code begining with H.
There have also been several silvery-green tones, one of the nicest being Alpine Green Metallic of the late 80's. The name of the one used since 2000 or so is Seafrost, I believe. I am not at my desk so I cannot check the three-letter code for this colour - but it is indeed beautiful and was also offered on the XK for the 2006/07 cars (06 for the UK, 07 for most of the ROW).

 

A bit more on colours: Seafrost (and that is the correct name) is as JagV8 said, a "Green-tinged silver" , very soft and very beautiful and fabulous on the XK (but the X150 looks great in almost any colour!). Despite the greenish tinge, it is not a green-based colour but a silver-based colour so the paint code does not begin with the signature green H; the code is MDV, M being the beginning letter for all the silver-based colours. Platinum, for example, is MDZ.
The other earlier green kI mentioned was Alpine Green Metallic, a silvery green, the code for which is HGF, because the base colour is green, not silver.