Old Glass Curio Cabinet

I picked up this 41" x 24" cabinet from a friend who had to move and had no room for it. He claims all the glass is worth $500, but I highly doubt it :D It is an olive green color with four curved glass sides, an oval glass top, one custom fit mirror bottom, and a thick custom fit glass shelf. It has two light bulbs with old cloth- wrapped wires. The flush mount lock is still intact, but missing the key and knob. Beautiful ornate borders around the glass and flourishes on all 4 legs. The only markings I've found are a number "12" on the bottom and another number "12" on the bottom front piece. I would absolutely love to find out ANY information on this lovely little cabinet if anyone out there can tell me an approximate time period, or country. I would only sell this if it's worth alot, but if not, I'm going to refurbish and keep it. I just don't want to quite yet until I find out! It's my new favorite thing to obsess about, so I've already bought lights, keys,paint, rub n buff, etc. I know it's a sin to refurbish an antique, so I need to know if it's a keeper, or a money maker lol.