Value of mint condition first pressing of Sgt. Pepper?

I have a mint condition first pressing (I think) copy of Sgt. Pepper's Lonely Hearts Club Band.  Vinyl is shiny and plays flawlessly, jacket is shiny with few indentations, and insert looks like new.  Any idea how much it might be worth.  Also, any idea as to how much value something like this gains over the years?  I'm thinking of giving it to my granddaughter (age 4) for her to cash in when she graduates high school.
Any input will be greatly valued.Russ
Take a look at for actual prices fetched at auction. Is it the UK mono first pressing? This one sold for about $1,900 in 2014.

You really need to be certain of pressing and condition.
Rule of thumb - if it looks like it hasn’t been played it’s probably not the 1st Pressing 😀
There tons of different copies/catalog#'s/etc but good place to start is to discogs
Look up the information in the matrix/runout area on Discogs to see what version you have, using the "find your version" tool.  Once you've done that, search the marketplace to see what other people think they are worth.  
I'm with GK on this one. 

As for value, doesn't have to be first pressing to be worth a lot. Just has to sound good. Really, really good.
thanks to everyone so far.  the album has been in my possession since July of 1967, so geoff's input isn't appropriate.
Mine is stereo, not mono, and I'll check it out and take notes after my granddaughter opens it on xmas eve.
I’ll give you $25 no questions asked. You could always listen to it. 

Stereo U.S. pressings of SPLHCB are VERY common, and worth no more than any other album from 1967, and actually less than many others that didn’t sell well (there were a lot of SPLHCB pressed and sold, and then not played much---it’s not a very good album ;-). Now if it was the Mono version it would be different story, especially a UK pressing.

The idea that original pressings of classic albums are ipso facto worth serious money is a myth believed only by those who aren’t into collecting enough to know any better. By the time your granddaughter graduates high school, this LP will be worth even less.

Mine is definitely an English pressing.  Might that make a difference?

An English pressing? Yes, worth more than a U.S.A. pressing, but not nearly as much a Mono LP, English or U.S.A. Do you have the included page of mustache cut-outs, etc., and the E.M.I. inner sleeve?

What determines the value of an LP is:

1- Supply versus demand.

2- Condition.

3- sound quality
But Tom Port has a lock on that.
Too many non record collectors over estimate the value of used records.

If the record is worth less than $50 it is not even worth selling.

You have to run an ad , pay fees, buy a shipping box, hassle with price, etc.

Very, very few records are worth more than $50.

Just keep your records and enjoy, or give them to someone that will play them.
In my experience, it's generally records from the 90s that were pressed in low volume that are now sought after by my generation of Gen-X'rs that are going for good money. Try to find a copy of Marilyn Manson's "Mechanical Animals" or "Antichrist Superstar" and you will see what I mean. Vinyl was the mainstream format in the 60's, 70's and into the 80's. The volume of pressings makes those albums worth less, certainly there are outliers on the older albums like certain pressing of Beatles albums going for thousands of dollars but they are thre exception in my experience.  Your milage may vary...
How does one find the "find your version" tool on discogs?
Yes but demand is the most important. I have super rare Jazz albums . One is in Goldmine for $800. The thing is the albums have no demand; hence no buyers for even $200.
Just punch in your album title, it will show in results say " all versions".
Hit that and it will then show you every version that is known submitted to Disccogs so far.
You can scroll down the list and click on any one of them for more detail.
Good luck
@gpgr4blu If you search for the album title from the Discogs main page, the first result that will come up is "all versions".  Click on that and the next page will show the track list of the album and below that, a list of all releases of the album. 

Below the track list and at the top right of the list of releases you'll see a box with a magnifying glass that says "Find Your Version".  Click on that and you can put the catalog number in to narrow down the results. 

I find that going to the dead wax and putting in as much information from there as you can narrows things down even further.  Usually there are photos of the album cover and labels, so you can compare to yours and see if they match, along with the pressing info in the dead wax.
I have a related question. Where can you find the criteria for determining if an LP is Very Good, Near Mint, Mint, etc.? I have lots of old records that I would like to find good homes for but definitely wouldn’t want to misrepresent anything.  
@woofman74 Goldmine or Google "discogs grading"
Give it to your granddaughter with a note asking her to keep it, and actually play it. It has more sentimental value than anything.
It’s likely just a run of the mill press that may sound good. There are still a bazillion out there.
A Brit mono is the only version to discuss.Maybe a sealed US version might have some value, but it’s not gonna be an Antiques Road Show find.
Hey Schubert, why don’t you go listen to some Wagner?
And tell Tchaikovsky the news
That was my (belly laugh) for today. Thanks!
OK:  I have checked all the markings on the record and jacket.

I will check all the resources the helpful responses have indicated, but here's the info I have:

It is made in Great Britain in 1967PCS 7027On the label it says YEX 637, but on the vinyl, 636.5.  The letters HTM are (what looks to be) etched on the inner circle of the vinyl.
I have only played this a few times; it looks like brand new and plays beautifully.

Any ideas?
The things you mention don’t mean anything in answering the question if it’s a first pressing. ’Made in Great Britain’, the publishing date 1967, the catalogue number PCS 7027 and the tape number YEX 637 (side 1) and 638 (side 2) are mentioned on just about every UK pressing. If the label is the Black/yellow parlophone label and it includes the text ’sold in UK, subject to resale price conditions, see price list’, than chances are you have a first pressing.

But the really important info is in the run out grooves. First pressings need to have the first matrix, which reads as YEX 637 -1 and YEX 638 -1 at 6 o’clock. Than it needs to have a first mother, to be read as ’1’ at 9 o’clock. Finally you need to check the stamper number at 3 o’clock, which uses the letters GRAMOPHLTD (G being first stamper, etc.). The earlier the better. Beatles records sold by the truck loads, so stampers codes with two or even three letters (e.g GAP = 136th stamper) are very common. If you have one letter stampers on both sides you have a very early first pressing.

First stereo pressings in mint condition are less valuable than mono, but still in the hunderds. However, you mention the letters HTM. These are mostly seen on EMI pressings of the mid 70’s, so if present it’s unlikely to be a first pressing.

Now THAT was an explanation, Edgewear! I purchased a 1st issue UK Sgt Pepper today and was all excited and congratulating myself. Then I read your post and noticed my copy has what looks like a GBP in the runout (along with a YEX 637-1 matrix). So although its a first issue its not a VERY early pressing. Still happy to have it though!