Hello again, and welcome back to Just Answer!My name is XXXXX XXXXX it will be my pleasure to assist you today.From the reviews I have read, it seems like a good read, but several readers had constructive criticism about certain facets of the book and a majority of them also claimed that the ending was disappointing. The criticisms were that it was too detailed and descriptions became boring due to this, many Italian words were used and if you don't know the language, it was frustrating, and it does have a romantic storyline which falls a little short. You can read these varying reviews, here: Reviews The average review seems to be 3.41 out of 5. This site is reliable, as I have read reviews here before reading a book and what most of the reviewers say has rung true. This is another good review which sums up and gives some examples of the prior referenced criticisms of the book: http://www.historicalnovels.info/Secret-of-the-Glass.html
Most readers also said it was a little difficult to 'get into', but once they overcame that, it was worth reading.I would definitely consider it adult reading, and if the person to whom you are considering giving it as a gift has an interest in historical romance novels and Italy, I believe it will be well-received.