I normally read up about woods I work, but if I didn't know what wood it is, a first thing I would note is the weight - oily or dense woods (naturally stable) are quite heavy. Second, I would apply a little bit of a deep penetrating oil (linseed or tung oil) and see if wood absorbs any. Naturally stable woods like ironwood, ebony, cocobolo will not absorb oil (or can be effectively stabilized for same reason). Some times you have woods that have good water repellent qualities, but are not heavy. Koa is a good example. I is relatively stable when dry (in Hawaii, some still build paddles out of it) but it is not heavy and will absorb oil.
Finishing oils won't make wood waterproof - for that you have to use poly (forms a film), but it will give wood some water resistance without forming a surface film like poly does.
This might be an incomplete answer, as I only worked a few woods that were selected for their stability. I have not worked amboyna, but have some on hand and will give it a try one day.
M