along the top of the barrel will be the makers name. If it says colt, then probably a colt. if it has an Italian name then a re-pro
Call Colt and they will tell you. Proofhouse.com has Colt sn data.
Comparison to one known to be real.
depends on which model and condition................
The Colt M4 Carbine .22 is a replica of the real M4 but in .22 caliber.
The 1851 Colt navy with serial # 112343 was produced in 1861. (98000-117999) about 1861
I believe they did. check with Colt - 1 800 962 2658
1861 Colt Revoler
Experience and books.
50- 200 usd
Depends on make, model, condition, and whether it is a real firearm, or a non-firing replica. Not enough information to answer.
Colt Army Model 1861
Metal, plastic, rubber, firing, non-firing?