Antique porcelain? hand painted? Miniature framed portrait

Thank you for any help you can provide. 

Item Description:
A finely detailed, oval-shaped hand-painted miniature portrait of a young woman, likely painted on porcelain or ivory, housed in a gilt metal or brass frame with hanging loop. The back is padded with pink moiré silk and includes a handwritten inscription in pencil that appears to reference a name, address, and the year “1825/7.” The portrait itself depicts a woman in 18th-century-style attire, adorned with a flowered hat and curls in powdered gray.

Medium:

• Likely watercolor or gouache on porcelain or ivory (a closer in-person inspection under magnification and raking light would confirm).
• Frame: Gilt metal, possibly brass.

Estimated Date:

• Based on attire, materials, and style, it may date from the mid-to-late 19th century (Victorian revival of 18th-century fashion), despite the handwritten 1825/7 possibly referring to a previous owner or sitter's date.
• These miniatures were commonly made as personal mementos, especially between 1780 and 1880.

Inscription Clues:

• Appears to read:
  “Caroline” (likely the subject’s name)
  “57. Bern Rd.” (possibly a street or collector's note)
  “1825/7” (possibly referencing a date or inventory/catalog ID)
• Suggests a European origin, possibly English, German, or French.

Condition:

• Very good, with only minor wear.
• No visible flaking or cracking to the portrait surface.
• Fabric backing shows some wear but remains intact.

Estimated Value:

• If the portrait is painted on porcelain: $125–$250 USD
• If it is painted on ivory, and 19th century: $250–$600+ USD depending on provenance, quality, and sitter (note: ivory restrictions affect sale in many regions).
• Miniatures without artist signature but of high craftsmanship still command moderate prices in estate and collector markets.

Recommendation:
For precise authentication and valuation:

• Have the piece examined under UV light and magnification by an antique portrait miniature specialist or a fine art auction house.
• Consider contacting a certified appraiser affiliated with ASA (American Society of Appraisers) or ISA (International Society of Appraisers).