To a Stamp Collector - nothing. A replica is just a copy; it's not the real thing, so it's basically worthless. As with anything, a product is worth just as much as someone is willing to pay for it. The problem is stamp collectors are more informed than the average person.
The only value these Gold Replicas have is that they are novelties. Companies sell them to people giving them the idea that they are worth money and that in the future they'll be worth lots more. The reality is that they have little to no value.
As for the value of the gold on them, the gold on those replicas is about one or two microns in thickness, that's just enough to cover the paper. So the value of gold on one stamp is a fraction of a fraction of a penny. Let's see - you could probably take over one hundred dollars worth of these "gold" replica stamps and not even get one penny's worth of gold off of them.
Since the resale value is low due to lack of intrinsic value and lack of demand, the market exists at eBay, flea markets, yard sales and such similar low cost (for the seller) venues.
What is the value of a sheet of Appollo 8 stamps?
That will depend on the specific stamps. Condition, face value, mint or used, heavy cancellations will all play into the value. You will have to consult a postage stamp catalog to find out the specifics.
There are 100's of George Washington stamps issued by the US Postal Office. I assume that you are referring to the 2 cent 'Carmine' stamps of the 1920's, there are too many factors in identifying this stamp issue to place a value on the stamp without special expert examination. There are variations, types, watermarks, cancellations, hidden marks, grading that can vary the value from cents to 1000's of dollars.
Yes, an address will affect the value. On older stamps (pre-1940's) it will not make much of a difference.
No, S&H Green Stamps are no longer redeemable today. The program, which was popular from the 1930s to the 1980s, ceased operations in the late 1990s. While some collectors may still possess old stamps, they hold no value or redeemable status in modern times.
I mail my letters with stamps from the 60's. Only high denominations and other oddities from this era can bring any value to the stamps. Use it as postage.
There were no Christmas Stamps issued by the post office in the 1940's. These may be some stamps created by a charity such as the American Lung Society to raise funds. There are collectors, but you'll have to identify the specific item and then research the collectors market.
Yokiti Yamamoto has written: 'Japanese postage stamps' -- subject(s): Postage stamps 'Japanese postage stamps (for philatelists)' -- subject(s): Postage-stamps
It means that your return envelope must have stamps stuck ON IT to the value of 1.05.
Bertram William Henry Poole has written: 'The stamps of the German empire' -- subject(s): Accessible book, Postage-stamps 'The stamps of the German empire' -- subject(s): Postage-stamps
This can be pretty difficult. Many different printing companies were used and the variations in perforations, watermarks and the printing plates are hard to determine. Take the time to read the identification guide for US stamps in the front of most catalogs. Once you figure out what stamp you are looking at, it will provide an estimated value.